If it is assumed that 60 percent of those who receive a questionnaire by mail will respond and 300 responses are needed, what is the minimum number of questionnaires that should be mailed?
A) 400
B) 420
C) 480
D) 500
E) 600
I feel there's gotta be a nifty quick trick here. Experts?
OG 2016 Percentage Question
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60 percent of those who receive a questionnaire by mail will respondstaunchMBAican wrote:If it is assumed that 60 percent of those who receive a questionnaire by mail will respond and 300 responses are needed, what is the minimum number of questionnaires that should be mailed?
A) 400
B) 420
C) 480
D) 500
E) 600
Rewrite as: 60 percent of receivers = responders
We want 300 responders, so rewrite as: 60 percent of receivers = 300
60% of what = 300?
Option #1) Check answer choices
A) 400
60% of 400 = 240 (nope, we want 300)
.
.
.
D) 500
60% of 500 = 300...works!!
Or option #2) algebra
60% of x = 300
0.6x = 300
x = 300/0.6
= 500
= D
Or...
60% of x = 300
0.6x = 300
(3/5)x = 300
x = (5/3)300
= 500
= D
Cheers,
Brent
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Of every 100 questionnaires that are mailed, 60 will yield responses, implying the following ratio:staunchMBAican wrote:If it is assumed that 60 percent of those who receive a questionnaire by mail will respond and 300 responses are needed, what is the minimum number of questionnaires that should be mailed?
A) 400
B) 420
C) 480
D) 500
E) 600
I feel there's gotta be a nifty quick trick here. Experts?
responses : mailed = 60:100 = 3:5 = 300:500.
Thus, to yield 300 responses, the number of questionnaires that must be mailed = 500.
The correct answer is D.
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Maybe just .6r = 300. Then multiply both sides by 10, so 6r = 3000 and r = 500.
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If we let x = the number of questionnaires that should be mailed, then x must satisfy 0.6x = 300. Then, x = 300/0.6 = 500.staunchMBAican wrote:If it is assumed that 60 percent of those who receive a questionnaire by mail will respond and 300 responses are needed, what is the minimum number of questionnaires that should be mailed?
A) 400
B) 420
C) 480
D) 500
E) 600
Answer: D
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60 percent of those who receive a questionnaire by mail will respondstaunchMBAican wrote:If it is assumed that 60 percent of those who receive a questionnaire by mail will respond and 300 responses are needed, what is the minimum number of questionnaires that should be mailed?
A) 400
B) 420
C) 480
D) 500
E) 600
I feel there's gotta be a nifty quick trick here. Experts?
Rewrite as: 60 percent of receivers = responders
We want 300 responders, so rewrite as: 60 percent of receivers = 300
60% of what = 300?
Option #1) Check answer choices
A) 400
60% of 400 = 240 (nope, we want 300)
.
.
.
D) 500
60% of 500 = 300...works!!
Or option #2) algebra
60% of x = 300
0.6x = 300
x = 300/0.6
= 500
= D
Or...
60% of x = 300
0.6x = 300
(3/5)x = 300
x = (5/3)300
= 500
= D
Cheers,
Brent
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Hi All,
We're told that it is assumed that 60 percent of those who receive a questionnaire by mail will respond and 300 responses are needed. We're asked for the MINIMUM number of questionnaires that should be mailed. We can answer this question with a bit of logic and TESTing THE ANSWERS.
To start, IF only 50% of people responded to the questionnaire, then we would need 600 mailings to generate 300 responses (since 50% of 600 = 300). However, since we're dealing with a 60% response rate, (.6)(600) = 360 - and that's far more responses than we actually 'need.' Thus, 600 is almost certainly NOT the answer. Logically, we need fewer than 600 questionnaires; looking at the answer choices, it would make sense to think about 500 next...
10% of 500 = 50
60% of 500 = (6)(50) = 300
That is an exact match for what we were told, so this MUST be the answer.
Final Answer: D
GMAT assassins aren't born, they're made,
Rich
We're told that it is assumed that 60 percent of those who receive a questionnaire by mail will respond and 300 responses are needed. We're asked for the MINIMUM number of questionnaires that should be mailed. We can answer this question with a bit of logic and TESTing THE ANSWERS.
To start, IF only 50% of people responded to the questionnaire, then we would need 600 mailings to generate 300 responses (since 50% of 600 = 300). However, since we're dealing with a 60% response rate, (.6)(600) = 360 - and that's far more responses than we actually 'need.' Thus, 600 is almost certainly NOT the answer. Logically, we need fewer than 600 questionnaires; looking at the answer choices, it would make sense to think about 500 next...
10% of 500 = 50
60% of 500 = (6)(50) = 300
That is an exact match for what we were told, so this MUST be the answer.
Final Answer: D
GMAT assassins aren't born, they're made,
Rich