Fractions/Ratios/Decimals

[swerve]

A garage has a stock of side mirrors. The ratio of right side mirrors to left side mirrors is 5:3. Iris, a garage worker, attaches pairs of the left and right mirrors with an average with an adhesive tape until no more pairs can be made. If 30 right mirrors are left unpaired, how many left and right mirrors are there in the stock?

A. 240
B. 120
C. 80
D. 75
E. 48

The OA is B

Source: Economist GMAT

[Jay@ManhattanReview]

A garage has a stock of side mirrors. The ratio of right side mirrors to left side mirrors is 5:3. Iris, a garage worker, attaches pairs of the left and right mirrors with an average with an adhesive tape until no more pairs can be made. If 30 right mirrors are left unpaired, how many left and right mirrors are there in the stock?

A. 240
B. 120
C. 80
D. 75
E. 48

The OA is B

Source: Economist GMAT

Given the information, say there are 5x right and 3x left side mirrors.

=> No. of mirrors left = 5x – 3x = 2x

=> 2x = 30 => x = 15

So, there are a total of 5x + 3x = 8x = 8*15 = 120 mirros.

The correct answer: B

Hope this helps!

-Jay
_________________
Manhattan Review GMAT Prep

Locations: GMAT Classes Albuquerque | GMAT Tutoring | LSAT Prep Courses El Paso | Oakland Prep Classes SAT | and many more...

Schedule your free consultation with an experienced GMAT Prep Advisor! Click here.

[jasminekaur280]

With the information given to us, let’s say there are 5x right and 3x left sided mirrors.

Number of mirrors left = 5x – 3x = 2x

2x = 30 => x = 15

Hence, there are a total of 5x + 3x = 8x = 8*15 = 120 mirrors.

Therefore the correct answer is B

[Scott@TargetTestPrep]

A garage has a stock of side mirrors. The ratio of right side mirrors to left side mirrors is 5:3. Iris, a garage worker, attaches pairs of the left and right mirrors with an average with an adhesive tape until no more pairs can be made. If 30 right mirrors are left unpaired, how many left and right mirrors are there in the stock?

A. 240
B. 120
C. 80
D. 75
E. 48

The OA is B

Solution:

Since the ratio of right side mirrors to left side mirrors is 5 : 3, we can let 5x = the number of right side mirrors and 3x = the number of left side mirrors. We can create the equation:

5x - 3x = 30

2x = 30

x = 15

Therefore, there are a total of 5(15) + 3(15) = 120 mirrors.

Answer: B