Page 184 - Start Up Mathematics_8 (Non CCE)

\ Profit = S.P. – C.P. = ` (1,610 – 1,400) = ` 210

Ê Profit ˆ Ê 210 ˆ
\ Profit % = Á Ë C.P. ¥100 % = Á Ë1 400, ¥100 % = 15%
˜
˜
¯
¯
Hence, the profit% = 15%
Example 12: Anuradha purchased some buttons at 3 for ` 5 and sold them at 5 for ` 12. She gained ` 143
in all. How many buttons did she purchase?
Solution: Let the number of buttons purchased by Anuradha be x.
C.P. of 3 buttons = ` 5

5
fi C.P. of 1 button = `
3
Ê 5 ˆ 5x
fi C.P. of x buttons = ` Á Ë 3 ¥ x = ` 3
˜
¯
S.P. of 5 buttons = ` 12

12
fi S.P. of 1 button = `
5

ˆ
fi S.P. of x buttons = ` Ê 12 ¥ x = ` 12x
˜
Á
Ë
¯
5
5
Since she had a profit
12x 5x Ê 36x - 25xˆ 11x
\ Profit = ` – ` = ` Á ˜ = `
5 3 Ë 15 ¯ 15
Profit given = ` 143
11x 143 15¥
fi = 143 fi x = = 195
15 11
Hence, Anuradha purchased 195 buttons.

EXERCISE 12.1

1. Prachi bought a bangle box for ` 350. She sold it for ` 425. Find her profit percent.
2. Heena lost ` 15 by selling a saree for ` 500. Find the loss percent.
3. A merchant bought 10 kg of rice at ` 70 per kg. He sold 5 kg at ` 100 per kg and the remaining at
` 80 per kg. Find his profit and the profit percent.
4. The selling price of 10 books is equal to the cost price of 12 books. Find the profit percent.
5. A fruit seller buys mangoes at ` 350 per hundred and sells them at ` 48 per dozen. Find his profit or
loss percent.
6. Rajesh bought a sofa set for ` 6,500 and paid ` 150 for its transportation. He then sold it for ` 7,500.
Find his profit percent.
7. A reduction of 20% in the price of flour enables Akriti to buy an extra 5 kg of it for ` 320. Find
(a) the original price per kg (b) the reduced price per kg.
8. A dishonest shopkeeper professes to sell sugar at its cost price, but uses a weight of 980 g for 1 kg.
Find his profit percent.
9. Sonika sells two jewellery boxes for ` 1,400 each. On one she earns a profit of 10% and on the other
suffers a loss of 10%. Find her overall profit or loss percent.

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