2014 CEMC Gauss (Grade 8) Problems/Problem 7

Problem

How many prime numbers are there between $10$ and $30$ ?

$\text{ (A) }\ 4\qquad\text{ (B) }\ 7\qquad\text{ (C) }\ 6\qquad\text{ (D) }\ 3\qquad\text{ (E) }\ 5$

Since there aren't very many prime numbers in the range from $10$ to $30$ , we can simply list them all:

$11, 13, 17, 19, 23, 29$

There are $6$ numbers in this list. Thus, the number of prime numbers between $10$ and $30$ is $\boxed {\textbf {(C) } 6}$ .

~anabel.disher

2014 CEMC Gauss (Grade 8) (Problems • Answer Key • Resources)
Preceded by Problem 6	Followed by Problem 8
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CEMC Gauss (Grade 8)