In a certain store, the ratio of part-time workers to full-time workers is 2 to 5. If 4 part-time workers were hired,

BTGmoderatorDC wrote: ↑

Tue Mar 03, 2020 8:10 pm

In a certain store, the ratio of part-time workers to full-time workers is 2 to 5. If 4 part-time workers were hired, then the ratio would be 3 to 5. How many workers does the store have?

(A) 11

(B) 12

(C) 21

(D) 28

(E) 35

OA D

Source: Veritas Prep

Say the no. of part-time workers is p and the no. of full-time workers is f; thus, we have

p/f = 2/5;

After the addition of 4 part-time workers, the revised ratio = (p +4)/f = 3/5

=> p/f + 4/f = 3/5.

Pluuing-in the value of p/f, we get p/f + 4/f = 3/5 => 2/5 + 4/f = 3/5 => f = 20.

From p/f = 2/5 and f = 20, w ehave p = 8.

Thus, p + f = 8 + 20 = 28.

The correct answer: D

Hope this helps!

-Jay
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BTGmoderatorDC wrote: ↑

Tue Mar 03, 2020 8:10 pm

In a certain store, the ratio of part-time workers to full-time workers is 2 to 5. If 4 part-time workers were hired, then the ratio would be 3 to 5. How many workers does the store have?

(A) 11

(B) 12

(C) 21

(D) 28

(E) 35
OA D

Source: Veritas Prep

We can let the number of part-time and full-time workers be 2x and 5x, respectively. We can create the equation:

(2x + 4)/(5x) = 3/5

5(2x + 4) = 3(5x)

10x + 20 = 15x

20 = 5x

4 = x

So there are 2(4) = 8 part-time workers and 5(4) = 20 full-time workers, and therefore, there are 28 workers in the store.

Answer: D