GRE Prep Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized
for You
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
If r = 3s, s = 5t, t = 2u, and u ≠ 0, what is the value of
[#permalink]
04 Oct 2018, 07:23
04 Oct 2018, 07:23
Expert Reply
3
Bookmarks
00:00
Question Stats:
77% (01:19) correct
22% (01:47) wrong based on 113 sessions
Hide Show timer Statistics
If r = 3s, s = 5t, t = 2u, and u ≠ 0, what is the value of \(\frac{rst}{u^3}\) ?
A. 30
B. 60
C. 150
D. 300
E. 600
A. 30
B. 60
C. 150
D. 300
E. 600
Retired Moderator
Joined: 10 Apr 2015
Posts: 6218
Given Kudos: 136
Re: If r = 3s, s = 5t, t = 2u, and u ≠ 0, what is the value of
[#permalink]
04 Oct 2018, 13:53
04 Oct 2018, 13:53
2
1
Bookmarks
Carcass wrote:
If r = 3s, s = 5t, t = 2u, and u ≠ 0, what is the value of \(\frac{rst}{u^3}\) ?
A. 30
B. 60
C. 150
D. 300
E. 600
A. 30
B. 60
C. 150
D. 300
E. 600
A quick way to handle this question is to find values of r, s, t, and u that satisfy all given conditions, and then plug those values into rst/u³
GIVEN: t = 2u
Let u = 1 and t = 2
GIVEN: s = 5t
So, s = 5(2)
Evaluate to get: s = 10
GIVEN: r = 3s
So, r = 3(10)
Evaluate to get: r = 30
We're all set!
rst/u³ = (30)(10)(2)/(1³)
= 600/1
= 600
Answer: E
Cheers,
Brent
Re: If r = 3s, s = 5t, t = 2u, and u ≠ 0, what is the value of
[#permalink]
11 Jan 2021, 12:56
11 Jan 2021, 12:56
1
1
Bookmarks
All of the answer choices can be rewritten in terms of u. If t = 2u, then s = 10u and r = 30u. Thus, the equation can be rewritten as (30u)(10u)(2u)/u^3, or 600u^3)/u^3. The u^3 terms cancel each other out and we are left with 600. Thus the correct answer is E.
