The lake’s waterlily
Logic
Level
1
There is a lake, the first day grows a waterlily, and every day they get doubled. If after 60 days the lake’s completely covered, after how many days it had been covered for a half?
The answer is 59.
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If it takes 60 days to cover it then 2^60 waterlilies are there. Given that 2^59 times 2 = 2^60 then half of 2^60 is 2^59 and it took 59 days