A certain city owns 298 buses, whose routes are . . . . . .

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A certain city owns 298 buses, whose routes are divided into three zones. At a given time, if q buses are in the blue zone, r buses are in the red zone, s buses are in the green zone, and t buses are in garages, how many buses are in the green zone?

(1) The ratio of q to r to s is 4:6:7 and 26 buses are in garages.

(2) q = 64

The OA is the option E.

With both statements is not sufficient to get an answer here? Experts, can you help me, please? I am confused.

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by DrMaths » Wed Jan 17, 2018 5:50 am
If we change the letters to match the words (B = Blue, R = Red, G = Green, H = Housed (in garages)), its easier to see.
Now, here are the facts presented to us:
(3) B+R+G+H =298

Reworded:
(1) B:R:G=4:6:7, plus H =26
(2) B = 64

Using (3) (with (1)) only, we get B + R + G = 298-26 = 272 and G = 7/17 x 272 = 112, so (3) is sufficient.

Using (2) (with (3)) only, then all we know is that 64 + R + G + H = 298, which has too many variables, so is NOT sufficient.

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TTT

by uce08 » Thu Jan 18, 2018 6:18 am
Vincen wrote:A certain city owns 298 buses, whose routes are divided into three zones. At a given time, if q buses are in the blue zone, r buses are in the red zone, s buses are in the green zone, and t buses are in garages, how many buses are in the green zone?

(1) The ratio of q to r to s is 4:6:7 and 26 buses are in garages.

(2) q = 64

The OA is the option E.

With both statements is not sufficient to get an answer here? Experts, can you help me, please? I am confused.



B+r+g=298-26=272

as the ratio of b:r:g=4:6:7

then no of green buses is 7/17*272=112

please mention where i went wrong

as per me ans is A

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by ErikaPrepScholar » Tue Jan 23, 2018 5:58 am
Hey folks,

This isn't a great question because it isn't clear whether or not the garages are inside the different zones. So maybe all of the garages don't have a zone. Maybe all of the garages are in the green zone. Maybe half of the garages are in the red zone and half are in the green zone.

If we assume that the garages are not in any zone, we can solve using Statement 1, making answer choice A. However, the OA relies on us assuming that the garages could be in one of the three zones.

A problem this ambiguous wouldn't show up on the GMAT, so it isn't very useful practice material.
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