Page 116 - ICSE Math 7

Profit = 16% of ` 23,200
16
= × ` 23,200 = ` 3,712
100
As Profit = S.P. – C.P.
\ S.P. = C.P. + Profit
= ` 23,200 + ` 3,712 = ` 26,912

Example 5: Tia gains ` 4,800 by selling an article at a profit of 24%. Find the selling price of the article.
Solution: Let ` x be the cost price of the article.
Profit
Profit% = × 100%
Cost price
4,800
\ 24 = × 100
x
4,800 ×100
⇒ x = = 20,000
24
As Profit = S.P. – C.P.
\ S.P. = C.P. + Profit = ` 20,000 + ` 4,800 = ` 24,800

Example 6: If the selling price of 8 pencils is equal to the cost price Maths Info
of 10 pencils, find the profit per cent. If C.P. and S.P. of different
Solution: Let the cost price of a pencil be ` 1. number of articles are given,
then to find profit or loss per
\ C.P. of 10 pencils = ` 1 × 10 = ` 10 cent, find C.P. and S.P. of equal

S.P. of 8 pencils = C.P. of 10 pencils = ` 10 number of articles.
Profit on selling 8 pencils = S.P. of 8 pencils – C.P. of 8 pencils
= ` 10 – ` 8 = ` 2
Profit 2
Profit% = × 100% = × 100% = 25%
Cost price 8
Example 7: A shopkeeper buys 80 eggs for ` 400 and sells them at the rate of 30 eggs for ` 112.50.
Find his profit or loss per cent.
Solution: C.P. of 80 eggs = ` 400
400
\ C.P. of 1 egg = ` 80 = ` 5
S.P. of 30 eggs = ` 112.50
112.50
\ S.P. of 1 egg = ` = ` 3.75
30
As C.P. of 1 egg > S.P. of 1 egg, therefore there is a loss.
Also, Loss = C.P. – S.P. = ` 5 – ` 3.75 = ` 1.25
Loss
Loss% = × 100%
Cost Price
1.25
= × 100% = 25%
5
Example 8: A florist bought 14 flowers for ` 224. For how much should he sell one flower to gain
25% profit?
Solution: Profit = 25% of ` 224
25
= × ` 224 = ` 56
100

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