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## Comment on

Car Options## A tip some of you might find

Total = A + B + C - exactly 2 - 2 (exactly 3) + none

Spoiler below!

In this question

=40+30+50-18-22+0

=120-40

=80

Make sure you know it thoroughly, its very easy to make a mistake.

You can find it on the GMAT club

## There are 2 such formulas:

There are 2 such formulas:

#1) Total = Group 1 + Group 2 + Group 3 - (sum of all 2 or more overlaps) + (in all 3 groups) + none.

#2) Total = Group 1 + Group 2 + Group 3 - (sum of members in EXACTLY 2 groups) - 2(All three groups) + none

I'm reluctant to discuss these formulas, since these equations are more likely to confuse than enlighten. I think it's MUCH safer to use Venn diagrams in these cases.

Cheers,

Brent

## Hi Ben,

I am a lil confused as I'm unsure of when to use the formula and when not to. And in the formula also, there are two formula's so not sure which one to use.

What is the best approach to handle such questions? With the formula or without?

## I'm not a big fan of those

I'm not a big fan of those two equations (in fact, I've never taken the time to memorize them).

Rest assured, the test-makers won't create a question that relies solely on either of those formulas.

I recommend that students solve these types of questions by drawing three overlapping circles.

## Hi Brent,

How would you solve this problem without using the formula? - https://gmatclub.com/forum/of-the-300-subjects-who-participated-in-an-experiment-using-virtual-re-134147.html

## Here's my full solution:

Here's my full solution: https://gmatclub.com/forum/of-the-300-subjects-who-participated-in-an-ex...