Pairs of Primes

Middle School Madness - June 29, 2020

Pairs of Primes Image

You have a box of counting numbers from 1 to 10 (inclusive).  You select one number from the box and place it back in the box.  You repeat this process by picking a number again.  How many possible pairs of numbers that can be selected sum to a prime number?  It is important to note that picking a 2 first and 3 second is a different pair from picking a 3 first and 2 second.

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