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## Comment on

Combining Solutions W and X## I solved using the same

## Perhaps you're being too

Perhaps you're being too artistic :-)

For me, the sketches add perhaps 10 seconds to the solution.

Cheers,

Brent

## Too fast wow! For the moment

## Getting faster at solving

Getting faster at solving questions can take a while. Be sure to master the content BEFORE trying to get faster. For more on this, read these two articles:

- http://www.gmatprepnow.com/articles/making-friends-time-gmat-%E2%80%93-p...

- http://www.gmatprepnow.com/articles/making-friends-time-gmat-%E2%80%93-p...

That said, one way to increase your speed is to take the time to review the responses from the experts on the questions I have linked to. These experts often model the steps one should take to answer questions quickly.

Question: "How do you respond to all our questions so fast?"

Answer: Magic!! :-)

## I did exactly the same way,

I don't know if I'm starting to make sense of these things in my mind. But, these sketching method helps to visualize things so easily. Your method is excellent, Dear Brent.

## You're absolutely right; we

You're absolutely right; we don't necessarily need the sketches to answer these kinds of questions. However, as you've noted, the visual representations make the problems easier to manage for many students.

Kudos to you!

Cheers,

Brent

## A faster approach is testing

So what I did was I figured out Solution W is 50 mL salt and 200 mL water = 250 mL total

I started with answer C:

100 mL solution X means --> 80 mL salt + 20 mL water

TOTAL solution volume = 250 mL + 100 mL = 350 mL

So the concentration of salt in the new solution = (80+50)/(350) = (130)/(350) = 37% --- But we need it to be 40% so we need more of solution X so Eliminate C as well as A and B

Then test D:

125 mL solution X means --> 100 mL salt + 25 mL water

TOTAL solution volume = 250 mL + 125 mL = 375 mL

So the concentration of salt in the new solution = (50+100)/(375) = (150)/(375) = 40%

Therefore, the answer is D

## That's a perfect approach -

That's a perfect approach - nice work!!!