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Example 8: By selling a jacket for `1600, Seema suffered a loss of 20%. At what price should she
sell the jacket to gain 10%?

Solution: SP of the jacket = `1600.
Percentage of loss = 20%.
 100   100  100
Therefore, its CP =   × SP =   × `1600 = × `1600 = `2000
 100 − L%   100 20 80
−
Now, if percentage of gain = 10%, then

+
 100 + P%   100 10 110
SP =   × CP =   × `2000 = × `2000 = `2200
 100   100  100
Thus, Seema should sell the jacket for `2200 to have a gain of 10%.
Example 9: Khushi purchases 10 dozen bananas at the rate of `3 per banana. She sold 60% of the
bananas at the rate of `4 per banana and the remaining at the rate of `2 per banana. Find her
profit or loss per cent.
Solution: CP of 10 × 12, i.e., 120 bananas = `3 × 120 = `360 (Since, 1 dozen = 12)
60
Since, she sold 60% of the bananas, i.e., × 120 = 72 bananas at the rate of `4 per banana.
100
So, SP of 72 bananas = `4 × 72 = `288
Quick Check
Now, SP of the remaining 120 – 72, i.e., 48 bananas = 48 × `2 = `96
Renu bought two sewing
Therefore, SP of all the bananas = `288 + `96 = `384 machines for `4500 each. She

Since, SP > CP, there is a profit. sold one at a loss of 8% and
the other at a profit of 15%.
Profit = SP – CP = `384 – `360 = `24 Find the selling price of each
Profit 24 machine. Also, find out the
Profit % = × 100% = × 100%
CP 360 total profit or loss.
20 2
= % or 6 %
3 3
2
Therefore, Khushi’s profit is 6 %.
3
Example 10: Fatima sold two coolers for `7,980 each. On selling one cooler she suffered a loss of
5% and on selling the other she gained 5%. Find her overall gain or loss % in the whole transaction.
Solution: SP of the first cooler = `7,980. Percentage of loss = 5%.

 100   100  100
Therefore, its CP =   × SP =   × `7,980 = × `7,980 = `8400
 100 − L%   100 5 95
−
Now, SP of the second cooler = `7,980. Percentage of profit = 5%.

 100   100  100
 × `7,980 =
Therefore, its CP =   100 + P%  × SP =  100 5 105 × `7,980 = `7600


+
Total SP of the two coolers = `7,980 × 2 = `15960
Total CP = `8400 + `7600 = `16000
Since, total CP > total SP, therefore, a loss of `(16000 – 15960) = `40 has been made.

Loss 40 1
Thus, Loss% = × 100% = × 100% = %
CP 16000 4

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