Question 338592
A “simple square” is any integer greater than 1 that has only three positive integer factors—itself,its square root, and 1.
Which of the following is a simple square? 
A. 121 B. 100 C. 81 D. 64 E. 33 



factor each of the choices
121 = 11^2 = 1 * 121 = 1 * 11 * 11 (3 positive integer factors)
100 = 10^2 = 2^2 * 5^2 = 1 * 4 * 25 = 1 * 2 * 2 * 5 * 5
81 = 9^2 = 1 * 3 * 27 = 1 * 3 * 3 * 3 * 3
64 = 8^2 = 2^2 * 4^2 = 1 * 8 * 8 = 1 * 2 * 2 * 2 * 2 * 2 * 2
33 = 1 * 3 * 11
33 is not a product of a whole number times itself like the other choices



the answer is A. 121