Find the sum of the primes between 100 and 200, inclusive, that are 1 or 2 more than a perfect square.

Guest Oct 16, 2020

edited by
Guest
Oct 16, 2020

#1**-1 **

Let's start by listing out the perfect squares that are between 100 and 200.

11^2=121

12^2=144

13^2=169

14^2=196

Now, let's see if the numbers that are 1 or 2 more than these squares are prime.

121+1=122 NOT PRIME

121+2=123 NOT PRIME

144+1=145 NOT PRIME

144+2=146 NOT PRIME

169+1=170 NOT PRIME

169+2=171 **PRIME**

196+1=197 **PRIME**

196+2=198 NOT PRIME

171+197=368

CalTheGreat Oct 16, 2020

#2**+1 **

Squares between 100 200 * inclusive* 100 121 144 169 196

101 197 add them together ! *** edited ***

ElectricPavlov Oct 16, 2020

#5**-1 **

EP, I think it says "BETWEEN 100 and 200. . ." Doesn't that mean not including 100 and 200?

CalTheGreat
Oct 17, 2020