Question

 a discount of 10% is given on the marked price of a book, the publisher gains 20%. If the discount is increased to 15%, then what will the gain be?​

Answer 1

Answer:

I think by Gain you mean Gain%.

Suppose the Marked price is 100 minus discount 10%

Sell Price (SP)= 100–10 = 90

Gain% = 20%

we know SP = {(100+Gain%)/100} x CP (Cost price)

So, CP = SP/{(100+Gain%)/100}

putting the values

CP = 90/1.2

CP = 75

Now, discount is 15% so SP = 100–15 = 85

Gain = 85–75

Gain = 10

Gain% = (Gain x 100)/CP

So, Gain% = (1000/75) =13.33%