Today Puzzle #528
Puzzle No. 528 鈥� Monday 22 July
There are 61 craters on the moon named after scientists associated with The Royal Institution. 61 is a prime number. How many prime numbers are there smaller than 61?
Today’s #PuzzleForToday has been set by Dr Shaun Fitzgerald, Director of The Royal Institution
Click here for the answer
Prime numbers smaller than 61 are: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59. There are 17 prime numbers of value less than 61 … and 17 itself is a prime number!
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