9%
i looked it up
The volume of a cup of water increases by 10% when it turns to ice. By how
much does the volume of ice decrease after it melts completely to water again?
2 answers
1 cup = 236.6 mL
10% increase is 236.6 x 0.1 = 23.66 mL to make the total 260.3 mL as ice.
Whenit melts it goes back to 238.6 which is a difference of 23.66 so as a percentage that is 23.66/260.3 = 0.0908 which I would round to 0.091 and multiply by 100 to get 9.1% decrease.
10% increase is 236.6 x 0.1 = 23.66 mL to make the total 260.3 mL as ice.
Whenit melts it goes back to 238.6 which is a difference of 23.66 so as a percentage that is 23.66/260.3 = 0.0908 which I would round to 0.091 and multiply by 100 to get 9.1% decrease.