After completing a sales training program, Vincenzo shared h

Question

After Vincenzo completed a sales training program, his sales increased by \(\tfrac{1}{2}\). Prior to the training program, his sales accounted for \(\tfrac{1}{10}\) of the company’s total sales; after the program, they accounted for \(\tfrac{1}{8}\) of the total.

By what fraction did his colleagues’ sales increase?

A) \(\tfrac{1}{8}\)
B) \(\tfrac{3}{20}\)
C) \(\tfrac{1}{6}\)
D) \(\tfrac{3}{16}\)
E) \(\tfrac{1}{5}\)

A)  	frac{1}{8} 
B)  	frac{3}{20} 
C)  	frac{1}{6}  
D)  	frac{3}{16} 
E)  	frac{1}{5}

stne · Answer

C = Sales of his colleagues 
S= Vincenzos' sales before training.

Before training :

s = \frac{1}{10}(c+s)

10s=c+s  , \hspace{1mm}    c=9s

After training:

1.5s = \frac{1}{8}(c+1.5s)

12s=c+1.5s

c=10.5s

Fractional increase in  c= \frac{1.5}{9}= \frac{1}{6}

Ans C

Hope it helped.

Rishm · Answer

If you divide the entire sales, you will get 3/20 but if u divide it by the sales of the colleagues only - it will come to 1/6 (which is the right answer) - this is the trap most of them get into, it almost got me too.

snig264 · Answer

Hi, But why do we have to divide it by colleagues? as it wasnt mentioned clearly anywhere

After completing a sales training program, Vincenzo shared h

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After completing a sales training program, Vincenzo shared h

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