Given the inequalities above, which of the following CANNOT be the value of \(r?\)

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Gmat_mission wrote:
Sat Jun 06, 2020 5:13 am
\(3r \leq 4s+5\)
\(|s| \leq 5\)

Given the inequalities above, which of the following CANNOT be the value of \(r?\)

A. –20
B. –5
C. 0
D. 5
E. 20

[spoiler]OA=E[/spoiler]

Source: Official Guide
We rewrite the absolute value inequality for s as -5 ≤ s ≤ 5. If s = -5 (i.e., the smallest value it can be), then we have:

3r ≤ 4(-5) + 5

3r ≤ -15

r ≤ -5

If s = 5 (i.e., the largest value it can be), then we have:

3r ≤ 4(5) + 5

3r ≤ 25

r ≤ 25/3 = 8⅓

Therefore, we see that r can be any of the values in the given choices except 20.

Answer: E

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