Answers

2014-05-10T15:01:13+05:30
289,361,529,841,961 are the no.s having three factors between 200 and 1000.
if u square the primes,we get no.s with exactly three factors.
1 5 1
2014-05-12T08:16:43+05:30
There are 5 no. between 200 and 1000  which have exactly three factors 
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