If the number of red marbles is three . . . .

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If the number of red marbles is three times the number of green marbles in a bowl of marbles with only two colors of marbles, what is the ratio of the green marbles to all the marbles?

A. 1 : 3
B. 1 : 4
C. 3 : 4
D. 3 : 1
E. 4 : 1

The OA is B.

Why is B? Shouldn't it be A? I got confused.

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by DavidG@VeritasPrep » Fri Dec 15, 2017 8:14 am
VJesus12 wrote:If the number of red marbles is three times the number of green marbles in a bowl of marbles with only two colors of marbles, what is the ratio of the green marbles to all the marbles?

A. 1 : 3
B. 1 : 4
C. 3 : 4
D. 3 : 1
E. 4 : 1


The OA is B.

Why is B? Shouldn't it be A? I got confused.
If there are 3 times as many red marbles as green marbles, then we can designate the red marbles as 3x and the green marbles as x.

Red marbles: 3x
Green marbles: x
Total: 4x

Ratio of Green: Total = x:4x = 1:4.. The answer is B ('A' would be the ratio of Green:Red not Green:Total)
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by Scott@TargetTestPrep » Tue Sep 24, 2019 10:23 am
VJesus12 wrote:If the number of red marbles is three times the number of green marbles in a bowl of marbles with only two colors of marbles, what is the ratio of the green marbles to all the marbles?

A. 1 : 3
B. 1 : 4
C. 3 : 4
D. 3 : 1
E. 4 : 1

The OA is B.

Why is B? Shouldn't it be A? I got confused.
The ratio of red to green marbles is 3 : 1, so the ratio of green to total is 1 : (3 + 1) = 1 : 4.

Answer: B

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