BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

A 400 milliliter solution is 20% alcohol by volume. If 100 milliliters of water is added, what is the new concentration

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Legendary Member
Posts: 2276
Joined: Sat Oct 14, 2017 6:10 am
Followed by:3 members

A 400 milliliter solution is 20% alcohol by volume. If 100 milliliters of water is added, what is the new concentration

by VJesus12 » Sat May 30, 2020 3:17 pm

Timer

00:00

Your Answer

A

B

C

D

E

Global Stats

A 400-milliliter solution is 20% alcohol by volume. If 100 milliliters of water is added, what is the new concentration of alcohol, as a percent of volume?

(A) 5%
(B) 10%
(C) 12%
(D) 12.5%
(E) 16%

[spoiler]OA=E[/spoiler]

Source: Manhattan GMAT
Top
Source: — Problem Solving |
Junior | Next Rank: 30 Posts
Posts: 15
Joined: Sat May 30, 2020 10:48 pm

Re: A 400 milliliter solution is 20% alcohol by volume. If 100 milliliters of water is added, what is the new concentrat

by orthodoxparadox » Sat May 30, 2020 11:31 pm
Initially, the solution is \(20\%\) alcohol by volume.

This means that out of 400 ml of the solution,
Volume of alcohol = $$\frac{20}{100}\ \cdot\ 400\ =\ 80$$

Since, we add 100ml water to this solution, the volume of solution becomes 500ml, but the volume of alcohol does not change.

So, now the concentration of alcohol is \(\frac{80}{500}\ \cdot\ 100\ =\ 16\%\ \) E
Top
Post new topic Post Reply
• Page 1 of 1