Vincen wrote:Running at the same constant rate, "a" identical machines can produce a total of 120 bolts per minute. At this rate, how many bolts could 4 such machines produce in 5 minutes?
(A) a/6
(B) a/600
(C) 150/a
(D) 480/a
(E) 2,400/a
Let a=1, implying that 1 machine produces 120 bolts per minute.
Since 1 machine produces 120 bolts per minute, the rate for 4 machines = 4*120 = 480 bolts per minute.
At a rate of 480 bolts per minute, the number of bolts produced by the 4 machines in 5 minutes = rt = 480*5 = 2400 bolts. This is our target.
Now plug a=1 into the answer choices to see which yield the target value of 2400.
Only
E works:
2400/a = 2400/1 = 2400.
The correct answer is
E.
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
