What is the value of n in the equation: $$-25+19+n=s?$$

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What is the value of n in the equation: $$-25+19+n=s?$$

by BTGmoderatorLU » Fri Aug 27, 2021 5:26 am

00:00

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Source: Official Guide

What is the value of n in the equation: $$-25+19+n=s?$$

1) s = 2
2) n / s = 4

The OA is D

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Re: What is the value of n in the equation: $$-25+19+n=s?$$

by [email protected] » Sat Aug 28, 2021 6:43 am

00:00

A

B

C

D

E

Global Stats

BTGmoderatorLU wrote:
Fri Aug 27, 2021 5:26 am
Source: Official Guide

What is the value of n in the equation: $$-25+19+n=s?$$

1) s = 2
2) n / s = 4

The OA is D
Given: -25 + 19 + n = s
Simplify: -6 + n = s
Add 6 to both sides to get: n = s + 6

Target question: What is the value of n?

Statement 1: s = 2
We already know that n = s + 6
Replace s with 2 to get: n = 2 + 6 = 8
The answer to the target question is n = 8
Since we can answer the target question with certainty, statement 1 is SUFFICIENT

Statement 2: n/s = 4
Multiply both sides by s to get: n = 4s
Divide both sides by 4 to get: n/4 = s

We already know that n = s + 6
Replace s with s with n/4 to get: n = n/4 + 6
Multiply both sides by 4 to get: 4n = n + 24
Subtract n from both sides to get: 3n = 24
Solve, n = 8
The answer to the target question is n = 8
Since we can answer the target question with certainty, statement 2 is SUFFICIENT