# GRE Question regarding two quantities

These are sample questions

The question states this

w > 1

....Quantity A..............................Quantity B

7w - 4 ........................................ 2w + 5

So i started pluging in numbers. Started from 2 and onwards and in each case the A was bigger. However, the book as tried to solved the inequality. so that the final equation because

$w ? \frac{9}{5}$

The question gives this equation and then ask to pick one option from below

A. Quantity A is greater

B. Quantity B is greater

C. The quantities are equal

D. Relationship can't be determined from given information

In that case, any thing which is less than 1.7 would have a different result.

Now the question is, in GRE, for these kind of question. Is it safe to assume that when we are plugging in numbers we should always plug in decimals? Is there any rule of thumb for these sort of questions?

• What did the question ask for exactly? – Manish Kundu Jan 10 '18 at 17:28
• I would say to solve it the way the your book did. Guessing and checking is always going to be prone to error. If you do the manipulations correctly, you should be able to simplify equations like this down and determine the answer exactly. Also, you should include the whole question. From my memory of the GRE, I assume this was a multiple choice question, asking whether A>B, A<B, or that neither is true over the whole range. – Tyberius Jan 10 '18 at 17:29
• I have upadted the quesiton with those "MCQ". But the question that i am asking is not "How to solve". Question i am asking is to that IF i chose to plug in numbers, is it safe to assume that "decimal" is the right choice? – Em Ae Jan 10 '18 at 19:15

## 1 Answer

Plugging in the numbers is an easy and at many times reliable technique, but with the emphasize on "at many times" so your safest bet is to always solve the actual equation especially if it's as straight forward as this example.