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If r = 3s, s = 5t, t = 2u, and u ≠ 0, what is the value of
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04 Oct 2018, 07:23
04 Oct 2018, 07:23
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78% (01:19) correct
21% (01:47) wrong based on 114 sessions
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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
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Posts: 6218
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Re: If r = 3s, s = 5t, t = 2u, and u ≠ 0, what is the value of
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04 Oct 2018, 13:53
04 Oct 2018, 13:53
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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
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11 Jan 2021, 12:56
11 Jan 2021, 12:56
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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.
