Number Properties Pg. 170

[cesarcontrerasg]

Hi,

I was solving the Hard Practice Question Set in the Number Properties guide (Pg. 170), when a question popped up.

The question in matter (question number 9) says that x squared/4 is an integer greater than 50, and requires us to find the smallest possible value for x squared. So I did, and I came up with 204 as an answer. Nonetheless, the solutions say that the correct answer is 256.

I understand the explanation, but please correct me if I'm wrong: The question says that x squared / 4 is an integer greater than 50, and my solution satisfies that condition (204/4 = 51). However, the question does not state that x (plain, not squared) should also be an integer... Am I supposed to take for granted that "both x and x squared/4" are integers, although not clearly stated?

Thanks for your help.

C

[esledge]

Hi Cesar,

Good catch! I edited that whole book recently, and I am kicking myself for missing that one. The explanation doesn't say explicitly that x must be an integer, but clearly that was assumed based on the statement that "...so x must be divisible by 2 (even)" and the testing of only integers for x. Without that assumption, your answer would be correct.

We'll fix it in a future edition. Thanks for bringing it to our attention.