What is the value of p?

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What is the value of p?

by M7MBA » Sat Mar 31, 2018 7:53 am
What is the value of p?

(1) p^2 = 100
(2) p = √100

The OA is B.

Why is not sufficient the first statement? Can someone help me? Thanks in advanced.
Source: — Data Sufficiency |

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by [email protected] » Sat Mar 31, 2018 12:04 pm
Hi M7MBA,

We're asked for the value of P. This question comes down to a couple of standard Arithmetic rules.

1) P^2 = 100

When dealing with SQUARED terms, there is almost always 2 solutions to a given equation. Here, those solutions are +10 and -10.
Fact 1 is INSUFFICIENT

2) P = √100

In contrast to squared terms, when we're given a SQUARE ROOT, there is ONLY ONE solution - the POSITIVE one. Thus, the one solution here is +10.
Fact 2 is SUFFICIENT

Final Answer: B

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