Question

A man purchase 560 pens and he classified them in 3 categories such that he will sell them at a profit of 12%, 16% and 20% respectively. He earned a profit of 13% on the first two categories and a profit of 15% on all the three categories. Then find the number of pens in the second category.​

Answer 1

100

category I = x

category II = y

category III = 560-x-y

profit on I,II,III

12x/100 ,16x/100 and 20.(560-x-y)/100

add all and equate them to (560x15)/100 i.e 84 which gives 2x+y=700 - 1

and 12x/100+16y/100 = 13(x+y)/100

which gives x=3y

so put x=3y in equation 1

You will get y = 100 and that is your answer

Answer 2

Answer:

12%. 16%. 13%. 20%

. 13% 15%

3. 1. 5. 2

300, 100, 160 is