The Abandoned Pool
Algebra
Level
1
There is a carpet of moss growing on an old pool. Everyday, it grows twice its size from the day before. Within a span of 40 days, the moss carpet takes the whole area of the square pool. On what day was it exactly half the size of the pool?
Day 2
Day 40
Day 20
Day 39
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Every day it doubles so the previous day it will be the half of it which is day 39 { 40 - 1 }