What is the sum of all the prime numbers between 10 and 30?
Answer and explanation
Correct answer: C. 112
- Step 1: The primes are 11, 13, 17, 19, 23 and 29.
- Step 2: 11 + 13 = 24, 24 + 17 = 41, 41 + 19 = 60, 60 + 23 = 83, 83 + 29 = 112.
Answer
112.
Why not the others: 101 leaves out 11, 123 counts 11 twice and 129 counts 17 twice.
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