Preservation Chance

Preservation Chance is a modifier which allows resources to be preserved when creating items, allowing for the creation of items at no cost to the player. When resource preservation triggers, the player will receive a notification stating "You managed to preserve your resources".

The chance to preserve resources only applies when creating items within a skill, it does not affect:

Potion dose preservation
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Summoning tablet preservation
Prayer point preservation
Rune Preservation in
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Magic
Ammo Preservation in
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Ranged
Dig site map excavation preservation in
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Archaeology

The preservation chance for all skills is capped at 80%, unless a modifier which increases the cap applies.

Like preservation, doubling helps create more output for the same input. But doubling does this by increasing the output for each action taken, while preservation increases the number of actions possible for each unit of input. For sources of doubling, see Skill Boosts#Doubling Boosts for global modifiers or the "Skill Boosts" section of a specific skill. See Double Loot for more about doubling in combat.

Sources

Below is a list of many things other than

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Mastery

bonuses and

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Summoning

synergies which provide a chance to preserve resources. Another notable mention is that the Crown of Rhaelyx gains 15% preservation chance (for a total of 25%) when the player has at least one Charge Stone of Rhaelyx within their Bank.

Source	Type	DLC	Preservation Bonuses	Other Modifiers
Error creating thumbnail: File missing Tier 2 - 1	Agility Obstacle 2	Error creating thumbnail: File missing	-10% Chance to Preserve Resources in Skills	+10% Accuracy Rating when fighting against Abyssal Damage +3% chance to double loot in Combat when fighting against Abyssal Damage +8% Maximum Hit when fighting against Abyssal Damage
Error creating thumbnail: File missing Pipe Balance	Agility Obstacle 3		+3% Chance to Preserve Resources in Skills	+10 Mining Node HP +3% chance to deal no damage to Essence Nodes in Mining +3% chance to deal no damage to Ore Nodes in Mining
Error creating thumbnail: File missing Coal Stones	Agility Obstacle 4		+3% Chance to Preserve Resources in Skills	-4% Skill XP for all Skills +20% GP gained from Thieving +10% Food Healing Value
Error creating thumbnail: File missing Mud Crawl	Agility Obstacle 4		+3% Chance to Preserve Resources in Herblore	+2% Herblore Mastery XP +2% Herblore Skill XP -10% base primary resource quantity gained in Farming
Error creating thumbnail: File missing Tier 4 - 3	Agility Obstacle 4	Error creating thumbnail: File missing	-10% Chance to Preserve Resources in Skills	+10% flat Abyssal Slayer Region effect negation +5% Damage to Slayer Tasks when fighting against Abyssal Damage +10% Global Abyssal Slayer Coins (except Item Sales) +5% Damage to Monsters in Abyssal Slayer Regions
Error creating thumbnail: File missing Rock Climb	Agility Obstacle 5		-10% Chance to Preserve Resources in Skills	+5% Chance to Double Items in Fishing +5% Chance to Double Items in Woodcutting +5% Chance to Double Items in Mining +5% Chance to Double Items in Thieving
Error creating thumbnail: File missing Tree Climb	Agility Obstacle 5		-10% Chance to Preserve Resources in Skills	+3% Mastery XP in all Skills +4% Skill XP for all Skills -10% Rune Preservation -10% Ammo Preservation
Error creating thumbnail: File missing Tree Hop	Agility Obstacle 6		+5% Chance to Preserve Resources in Skills	+5% Rune Preservation +5% Ammo Preservation
Error creating thumbnail: File missing Boulder Trap	Agility Obstacle 7		-20% Chance to Preserve Resources in Skills
Error creating thumbnail: File missing Runic Trail	Agility Obstacle 8		+5% Chance to Preserve Resources in Summoning -16% Chance to Preserve Resources in Herblore	+15% Chance to preserve Summoning Charges +3 base primary resource quantity gained in Summoning
Error creating thumbnail: File missing Sweltering Pools	Agility Obstacle 8		-20% Chance to Preserve Resources in Skills	+3% Cooking Mastery XP +10% Auto Eat Efficiency -3% Cooking Interval +10% Food Healing Value
Error creating thumbnail: File missing Ice Jump	Agility Obstacle 9		+10% Chance to Preserve Resources in Skills	+20 Maximum Hitpoints +5% Food Healing Value +5% Chance to Double Items Globally +10 Mining Node HP
Error creating thumbnail: File missing Lava Waterfall Dodge	Agility Obstacle 10		+10% Chance to Preserve Resources in Skills	+10% Chance To Preserve Prayer Points +5% Ammo Preservation +10% Rune Preservation
Error creating thumbnail: File missing Pit Maze	Agility Obstacle 11		-20% Chance to Preserve Resources in Skills	+3% Mastery XP for Melvor Realm only +15 Mining Node HP +2% chance to receive a Quality Superior Gem while Mining Gem Veins or Meteorite Ore
Error creating thumbnail: File missing Cave Waters	Agility Obstacle 12		-10% Chance to Preserve Resources in Herblore	-6% Mastery XP for Melvor Realm only +15% Chance To Preserve Potion Charge
Error creating thumbnail: File missing Monkey Trail	Agility Obstacle 12		-10% Chance to Preserve Resources in Skills	-5% Cooking Interval +10% Food Healing Value -6% Agility Skill XP +15% base primary resource quantity gained in Farming for Melvor Realm only
Error creating thumbnail: File missing Cave Trap	Agility Obstacle 13		-10% Chance to Preserve Resources in Skills	-50 Maximum Hitpoints +5% Chance To Preserve Potion Charge +5% Chance to preserve Summoning Charges
Error creating thumbnail: File missing Mountain Trail	Agility Obstacle 15		-20% Chance to Preserve Resources in Skills	-0.2s Smithing Interval -0.2s Fletching Interval -0.2s Crafting Interval +30% Chance to gain +1 additional resource in Smithing (Cannot be doubled) +30% Chance to gain +1 additional resource in Fletching (Cannot be doubled) +30% Chance to gain +1 additional resource in Crafting (Cannot be doubled) +3% chance to receive a Quality Superior Gem while Mining Gem Veins or Meteorite Ore
Error creating thumbnail: File missing Pillar of Skilling	Agility Pillar		+3% Chance to Preserve Resources in Skills	+2% Mastery XP in all Skills +3% Chance to Double Items Globally +10% base primary resource quantity gained in Farming for Melvor Realm only
Error creating thumbnail: File missing Abyssal Bear	Item (Summon1, Summon2)	Error creating thumbnail: File missing	+5% Chance to Preserve Resources in Herblore
Error creating thumbnail: File missing Abyssal Cooking Scroll	Item (Consumable)	Error creating thumbnail: File missing	-10% Chance to Preserve Resources in Cooking	+1 additional quantity of primary resource gained in Cooking for Abyssal Realm only (cannot be doubled)
Error creating thumbnail: File missing Abyssal Fletching Scroll	Item (Consumable)	Error creating thumbnail: File missing	-10% Chance to Preserve Resources in Fletching	+1 additional quantity of primary resource gained in Fletching for Abyssal Arrows nodes (Cannot be doubled) +1 additional quantity of primary resource gained in Fletching for Abyssal Bolts nodes (Cannot be doubled) +1 additional quantity of primary resource gained in Fletching for Abyssal Javelins nodes (Cannot be doubled)
Error creating thumbnail: File missing Abyssal Hourglass (Inverted)	Item (Weapon)	Error creating thumbnail: File missing	+10% Chance to Preserve Resources in Skills	+6% Mastery XP for Abyssal Realm only -1 additional quantity of primary resource gained globally (Cannot be doubled) -10% cost to produce Abyssal Realm Items in all Artisan Skills -6% Global Abyssal XP
Error creating thumbnail: File missing Abyssal Hourglass (Upright)	Item (Weapon)	Error creating thumbnail: File missing	-10% Chance to Preserve Resources in Skills	-6% Mastery XP for Abyssal Realm only +1 additional quantity of primary resource gained globally (Cannot be doubled) +10% cost to produce Abyssal Realm Items in all Artisan Skills +6% Global Abyssal XP
Error creating thumbnail: File missing Abyssal Pig	Item (Summon1, Summon2)	Error creating thumbnail: File missing	+10% Chance to Preserve Resources in Cooking
Error creating thumbnail: File missing Abyssal Salamander	Item (Summon1, Summon2)	Error creating thumbnail: File missing	+5% Chance to Preserve Resources in Smithing
Error creating thumbnail: File missing Abyssal Smithing Scroll	Item (Consumable)	Error creating thumbnail: File missing	-10% Chance to Preserve Resources in Smithing	+1 additional quantity of primary resource gained in Smithing for Abyssal Bars nodes (Cannot be doubled)
Error creating thumbnail: File missing Abyssal Summoning Scroll	Item (Consumable)	Error creating thumbnail: File missing	-10% Chance to Preserve Resources in Summoning	+5 additional quantity of primary resource gained in Summoning for Abyssal Realm only (cannot be doubled)
Error creating thumbnail: File missing Bear	Item (Summon1, Summon2)		+5% Chance to Preserve Resources in Herblore
Candelabra (Lit)	Item (Consumable)		+3% Chance to Preserve Resources in Skills	-3% Interval for all Non-Combat Skills +4% Non-Combat Skill XP +4% Mastery XP for Melvor Realm only
Cape of Completion	Item (Cape)		+20% Chance to Preserve Resources in Summoning	+5 additional quantity of Runes gained in Runecrafting (Cannot be doubled) +10 Flat HP Regen Bypass Slayer Area item requirements for areas that require less than level 100 Slayer -50% Prayer Point Cost for Prayers -15% Township Building Cost (Capped at -80%) +15% Chance to Double Items in Runecrafting -20% Melvor Realm Agility Obstacle Build Costs +5% Damage To Slayer Tasks +50% Ammo Preservation +1 base quantity when gaining Stardust from Astrology +1 base quantity when gaining Golden Stardust from Astrology +10 base primary resource quantity gained in Summoning -0.5s Thieving Interval -0.5s Crafting Interval +2% Global Perfect Cook chance +25% Mastery Pool XP Cap +100% chance to successfully Cook an item Rune providing items provide 2x as many runes +10% Chance to preserve Summoning Charges +100% GP gained from Thieving +10% GP gained from Agility x2 Items received from Fishing x2 Items received from Fletching x2 Items received from Herblore -15% Woodcutting Interval -15% Cooking Interval +25% Flat Slayer Area Effect Negation +1 Coal Ore per Ore Mined. (Item doubling does not apply) -50% Coal Costs for Smithing +150 Stealth while Thieving +100% chance to gain Coal Ore in Firemaking +100% chance to gain Ash in Firemaking +5% Skill XP for all Skills +25% base primary resource quantity gained in Farming
Cape of Completion (Atlas of Discovery)	Item (Cape)		+20% Chance to Preserve Resources in Cartography	+3 levels of the Brush Tool in Archaeology +3 levels of the Trowel Tool in Archaeology +3 levels of the Shovel Tool in Archaeology -30% Cartography survey interval +15% chance to preserve dig site map excavation actions -50% Cartography map upgrade interval -20 dig site map refinement cost +1 base primary resource quantity gained in Archaeology +3 levels of the Sieve Tool in Archaeology
Cartography Skillcape	Item (Cape)		+10% Chance to Preserve Resources in Cartography	-20% Cartography map upgrade interval -10 dig site map refinement cost
Chefs Bag	Item (Consumable)		+10% Chance to Preserve Resources in Cooking	+20% Chance to Double Items in Cooking
Clown Hat	Item (Helmet)		-10% Chance to Preserve Resources in Skills	+10% Mastery XP in all Skills -5% Skill XP for all Skills
Crown of Rhaelyx	Item (Helmet)		+10% Chance to Preserve Resources in Skills
Error creating thumbnail: File missing Magic Enhancement (Superior)	Item (Enhancement1, Enhancement2, Enhancement3)		+2% Chance to Preserve Resources in Skills	+6% Magic Max Hit +4% Rune Preservation
Error creating thumbnail: File missing Magic Enhancement 3	Item (Enhancement3)		+1% Chance to Preserve Resources in Skills
Error creating thumbnail: File missing Magic Enhancement 3 (Augmented)	Item (Enhancement3)		+2% Chance to Preserve Resources in Skills
Maximum Skillcape	Item (Cape)		+20% Chance to Preserve Resources in Summoning	+5 additional quantity of Runes gained in Runecrafting (Cannot be doubled) +10 Flat HP Regen Bypass Slayer Area item requirements for areas that require less than level 100 Slayer -50% Prayer Point Cost for Prayers -15% Township Building Cost (Capped at -80%) +15% Chance to Double Items in Runecrafting -20% Melvor Realm Agility Obstacle Build Costs +50% Ammo Preservation +1 base quantity when gaining Stardust from Astrology +1 base quantity when gaining Golden Stardust from Astrology +10 base primary resource quantity gained in Summoning -0.5s Thieving Interval -0.5s Crafting Interval +2% Global Perfect Cook chance +1 Coal Ore per Ore Mined. (Item doubling does not apply) +100% chance to successfully Cook an item +5% Damage To Slayer Tasks +10% Chance to preserve Summoning Charges +100% GP gained from Thieving +10% GP gained from Agility Rune providing items provide 2x as many runes -15% Woodcutting Interval -15% Cooking Interval x2 Items received from Fishing x2 Items received from Fletching x2 Items received from Herblore +25% Flat Slayer Area Effect Negation -50% Coal Costs for Smithing +150 Stealth while Thieving +100% chance to gain Coal Ore in Firemaking +100% chance to gain Ash in Firemaking +5% Skill XP for all Skills +25% base primary resource quantity gained in Farming
Peasant Shirt	Item (Platebody)		+8% Chance to Preserve Resources in Skills	-30% Global GP (except Item Sales)
Error creating thumbnail: File missing Pig	Item (Summon1, Summon2)		+10% Chance to Preserve Resources in Cooking
Ring of Wealth	Item (Ring, Passive)		-3% Chance to Preserve Resources in Skills	+7% Chance to Double Items Globally
Error creating thumbnail: File missing Salamander	Item (Summon1, Summon2)		+5% Chance to Preserve Resources in Smithing
Sturdy Fancy Quill	Item (Weapon)		+20% Chance to Preserve Resources in Cartography	-5% Cartography Interval +8% Cartography Skill XP +20% Chance to Double Items in Cartography
Summoning Scrolls	Item (Consumable)		+10% Chance to Preserve Resources in Summoning	+10% Chance to preserve Summoning Charges +15 base primary resource quantity gained in Summoning
Summoning Skillcape	Item (Cape)		+20% Chance to Preserve Resources in Summoning	+10% Chance to preserve Summoning Charges +10 base primary resource quantity gained in Summoning
Superior Cape of Completion	Item (Cape)		+25% Chance to Preserve Resources in Summoning	+8 additional quantity of Runes gained in Runecrafting (Cannot be doubled) +15 Flat HP Regen +5% of Maximum Hit added to Minimum Hit -75% Prayer Point Cost for Prayers -20% Township Building Cost (Capped at -80%) -30% Melvor Realm Agility Obstacle Build Costs +5% Melee Strength Bonus from Equipment +2 base quantity when gaining Stardust from Astrology +2 base quantity when gaining Golden Stardust from Astrology +1 base quantity when gaining Bird Nest from Woodcutting +20% chance to avoid the stun interval and damage in Thieving when failing a pickpocket attempt for {realmName} only +4% Global Perfect Cook chance +2 Coal Ore per Ore Mined. (Item doubling does not apply) +100% chance to successfully Cook an item +5% Ranged Strength Bonus from Equipment +10% Global Slayer Coins (except Item Sales) +150% GP gained from Thieving +20% GP gained from Agility +100% Chance to gain +1 additional resource in Fishing (Cannot be doubled) +100% Chance to gain +1 additional resource in Fletching (Cannot be doubled) +15% Chance to gain +1 additional resource in Crafting (Cannot be doubled) +100% Chance to gain +1 additional resource in Herblore (Cannot be doubled) +50% chance to gain +1 additional resource in Smithing for Bars nodes (Cannot be doubled) +270 Stealth while Thieving +100% chance to gain Charcoal in Firemaking +100% chance to gain Coal Ore in Firemaking +100% chance to gain Ash in Firemaking +10% Summoning Max Hit Rune providing items provide 4x as many runes +40% base primary resource quantity gained in Farming +5% Lifesteal +5% Magic Damage Bonus from Equipment +1% chance to gain 1 Lost Chest from Fishing for Melvor Realm only (Cannot be doubled) +75% Ammo Preservation +8% Damage To Slayer Tasks -75% Coal Costs for Smithing -0.8s Thieving Interval -0.8s Crafting Interval +20% Chance to Double Items in Farming +25% Chance to Double Items in Runecrafting +15% Chance to preserve Summoning Charges +35% Flat Slayer Area Effect Negation +5% Chance To Preserve Prayer Points +1 base primary resource quantity gained in Fletching for Gem-Tipped Bolts nodes +10 base primary resource quantity gained in Summoning for Melvor Realm only Bypass All Slayer Area item requirements +5% Chance To Preserve Potion Charge -20% Woodcutting Interval -25% Cooking Interval -10% Summoning Interval -10% Astrology Interval +5% Reflect Damage -20% Agility Pillar build costs +5% Chance to Preserve Food when eaten +5% Chance to find gem veins when Mining +8% Skill XP for all Skills +10% Rune Preservation x2 Items received from Fishing x2 Items received from Fletching x2 Items received from Herblore
Superior Cartography Skillcape	Item (Cape)		+20% Chance to Preserve Resources in Cartography	-50% Cartography map upgrade interval -20 dig site map refinement cost -30% Cartography survey interval
Superior Max Skillcape	Item (Cape)		+25% Chance to Preserve Resources in Summoning	+8 additional quantity of Runes gained in Runecrafting (Cannot be doubled) +15 Flat HP Regen +5% of Maximum Hit added to Minimum Hit -75% Prayer Point Cost for Prayers -20% Township Building Cost (Capped at -80%) -30% Melvor Realm Agility Obstacle Build Costs +5% Melee Strength Bonus from Equipment +2 base quantity when gaining Stardust from Astrology +2 base quantity when gaining Golden Stardust from Astrology +1 base quantity when gaining Bird Nest from Woodcutting +20% chance to avoid the stun interval and damage in Thieving when failing a pickpocket attempt for {realmName} only +4% Global Perfect Cook chance +2 Coal Ore per Ore Mined. (Item doubling does not apply) +100% chance to successfully Cook an item +5% Ranged Strength Bonus from Equipment +10% Global Slayer Coins (except Item Sales) +150% GP gained from Thieving +20% GP gained from Agility +100% Chance to gain +1 additional resource in Fishing (Cannot be doubled) +100% Chance to gain +1 additional resource in Fletching (Cannot be doubled) +15% Chance to gain +1 additional resource in Crafting (Cannot be doubled) +100% Chance to gain +1 additional resource in Herblore (Cannot be doubled) +50% chance to gain +1 additional resource in Smithing for Bars nodes (Cannot be doubled) +270 Stealth while Thieving +100% chance to gain Charcoal in Firemaking +100% chance to gain Coal Ore in Firemaking +100% chance to gain Ash in Firemaking +10% Summoning Max Hit Rune providing items provide 4x as many runes +40% base primary resource quantity gained in Farming +5% Lifesteal +5% Magic Damage Bonus from Equipment +1% chance to gain 1 Lost Chest from Fishing for Melvor Realm only (Cannot be doubled) +75% Ammo Preservation +8% Damage To Slayer Tasks -75% Coal Costs for Smithing -0.8s Thieving Interval -0.8s Crafting Interval +20% Chance to Double Items in Farming +25% Chance to Double Items in Runecrafting +15% Chance to preserve Summoning Charges +35% Flat Slayer Area Effect Negation +5% Chance To Preserve Prayer Points +1 base primary resource quantity gained in Fletching for Gem-Tipped Bolts nodes +10 base primary resource quantity gained in Summoning for Melvor Realm only Bypass All Slayer Area item requirements +5% Chance To Preserve Potion Charge -20% Woodcutting Interval -25% Cooking Interval -10% Summoning Interval -10% Astrology Interval +5% Reflect Damage -20% Agility Pillar build costs +5% Chance to Preserve Food when eaten +5% Chance to find gem veins when Mining +8% Skill XP for all Skills +10% Rune Preservation x2 Items received from Fishing x2 Items received from Fletching x2 Items received from Herblore
Superior Summoning Skillcape	Item (Cape)		+25% Chance to Preserve Resources in Summoning	-10% Summoning Interval +10% Summoning Max Hit +15% Chance to preserve Summoning Charges +10 base primary resource quantity gained in Summoning for Melvor Realm only
Error creating thumbnail: File missing Void Wisp	Item (Summon1, Summon2)	Error creating thumbnail: File missing	+5% Chance to Preserve Resources in Skills
Error creating thumbnail: File missing Gunter	Pet		+10% Chance to Preserve Resources in Runecrafting
Error creating thumbnail: File missing Puff, the Baby Dragon	Pet		+10% Chance to Preserve Resources in Smithing
The Monolith	Point of Interest		+5% Chance to Preserve Resources in Cartography	-5% Cartography map upgrade interval +5% chance to preserve dig site map excavation actions
Error creating thumbnail: File missing Error creating thumbnail: File missing D3	Skill Tree Node	Error creating thumbnail: File missing	+5% Chance to Preserve Resources in Herblore
Error creating thumbnail: File missing Crow Error creating thumbnail: File missing Salamander Synergy	Summoning Synergy		+10% Chance to Preserve Resources in Smithing +10% Chance to Preserve Resources in Runecrafting
Error creating thumbnail: File missing Pig Error creating thumbnail: File missing Crow Synergy	Summoning Synergy		+15% Chance to Preserve Resources in Cooking	+15% chance to preserve resources in Runecrafting when making Runes
Error creating thumbnail: File missing Pig Error creating thumbnail: File missing Devil Synergy	Summoning Synergy		-10% Chance to Preserve Resources in Firemaking -10% Chance to Preserve Resources in Cooking	+8% Firemaking Mastery XP +8% Cooking Mastery XP

Chance Cap

The preservation chance for all skills is capped at 80%. For a few skills, there exists bonuses which can increase this cap:

The
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Bear & Beaver synergy can increase the cap for
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Fletching by 5%
The
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Bear & Fox synergy can increase the cap for
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Herblore by 5%
The Herblore Preservation Scroll from
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Township can increase the cap for
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Herblore by 5%. This stacks with the above.

Calculating Gains

Let's say you have 120 bars, 80% resource preservation, and 0% doubling chance. If a dagger takes one bar to create, how many daggers would you create on average out of 120 bars?

The answer is [math]\displaystyle{ \frac{120}{1 - 80/100} = \frac{120}{0.2} = 600. }[/math]

The main idea behind resource preservation is that you can reuse the preserved resources to make more items, but those resources when used will themselves be preserved also.

Using the same example with 120 bars, you take 120 actions producing 120 daggers, but with 80% preservation you are left with [math]\displaystyle{ 120 \times 0.8 = 96 }[/math] bars.

Now you can use those 96 bars to do the same thing, and you will be left with [math]\displaystyle{ 96 \times 0.8 = 76.8 }[/math] bars on average.

Repeat that to infinity, and you will get the average number of daggers that you will produce from 120 bars.

But how do we calculate this number?

So the number of daggers produced is [math]\displaystyle{ 120 + (120 \times 0.8) + (120 \times 0.8 \times 0.8) +\cdots + (120 \times 0.8^n) }[/math] where [math]\displaystyle{ n }[/math] goes to infinity.

If we generalize and represent the number of starting resources ([math]\displaystyle{ 120 }[/math]) with [math]\displaystyle{ a }[/math] and the probability ([math]\displaystyle{ 0.8 }[/math]) with [math]\displaystyle{ r }[/math], the number of actions performed with [math]\displaystyle{ a }[/math] action's worth of starting resources and a resource preservation of [math]\displaystyle{ r }[/math] (where [math]\displaystyle{ 0 \le r \lt 1 }[/math]) can be expressed as follows:

[math]\displaystyle{ a + (a \times r) + (a \times r \times r) + \cdots + (a \times r^n) = \sum\limits^{\infty}_{n=0} ar^n }[/math]

This expression is an infinite geometric series, which can simply be expressed as [math]\displaystyle{ \displaystyle \lim_{n \to \infty}\tfrac{a(1 - r^n)}{1 - r} = \frac{a}{1 - r} }[/math].

So, coming back to our example where [math]\displaystyle{ a = 120 }[/math] and [math]\displaystyle{ r = 0.8 }[/math], we get [math]\displaystyle{ \frac{120}{1 - 0.8} = 600 }[/math].