warlock wrote:Three quarts of a bleaching chemical, Minum, contains 5 percent hydrogen peroxide and water. A different type of bleaching chemical, Maxim, which contains 20 percent hydrogen peroxide, will be mixed with the three quarts of Minum. How much of type Maxim should be added to the three quarts of Minum so that the resulting mixture contains 15 percent hydrogen peroxide?
A. 3 quarts
B. 3.75 quarts
C. 4.5 quarts
D. 6 quarts
E. 9 quarts
Can anyone explain me the procedure. thank you.
Another approach would be to plug in the answers.
Since the percentage in the mixture (15%) is closer to the percentage in Maxim (20%), the mixture must be more than 1/2 Maxim.
Eliminate A.
Of the remaining answer choices, we should start with the next greatest that is an integer.
Amount of hydrogen peroxide in Minum = .05(3) = .15.
Answer choice D: 6 quarts Maxim.
Amount of hydrogen peroxide in Maxim = .2(6) = 1.2 .
Total hydrogen peroxide/Total mixture = (.15+1.2)/(3+6) = 1.35/9 = 135/900 = 15/100 = 15%.
Success!
The correct answer is
D.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at
[email protected].
Student Review #1
Student Review #2
Student Review #3
