Page 186 - Start Up Mathematics_8 (Non CCE)

Ê 100 10- ˆ Ê 90 ˆ
= ` Á 100 ¯ ˜ × 9,600 = ` Á Ë 100 ¥ 9 600, ˜ = ` 8,640
Ë
¯
Profit = S.P. – C.P. = ` (8,640 – 8,000) = ` 640
Profit 640
=
Profit % = ¥100 = ¥ 100 8%
C.P. 8 000,
\ Selling price of the refrigerator = ` 8,640 and profit % = 8%
Example 16: A shopkeeper offers 10% discount on all his goods and still makes a profit of 17%. If an item
is marked ` 260, find its cost price.
Solution: Let the cost price of the item be ` x.
Profit % = 17%

Ê 100 + Profit% ˆ Ê 100 17+ ˆ
S.P. = Á Ë 100 ˜ ¯ × C.P. = ` Á Ë 100 ¯ ˜ ¥ x

117
S.P. = ` x ...(1)
100
M.P. of the item = ` 260

Discount % = 10%
10
fi Discount = 10% of 260 = × 260 = ` 26
100
\ S.P. = M.P – Discount = ` (260 – 26)
S.P. = ` 234 ...(2)
From (1) and (2), we get

117x
= 234
100
234 100¥
fi x = = ` 200
117
\ Cost price of the item = ` 200

Example 17: A table marked at ` 15,000 is available for ` 14,400. Find the discount and the discount
percent. (NCERT)

Solution: M.P. of the table = ` 15,000
S.P. of the table = ` 14,400

\ Discount = M.P. – S.P. = ` (15,000 – 14,400) = ` 600

Ê Discount ˆ Ê 600 ˆ
fi Discount % = Á M.P ¥100 % = Á Ë 15 000, ¥ 100 % = 4%
˜
˜
Ë
¯
¯
Hence, the discount on the table is ` 600 and discount % is 4%.
Example 18: A sports dealer sells cricket bats, costing ` 980 each. At what price must he mark each of
them so as to make a profit of 12%, after giving a discount of 20%?
Solution: C.P. of a cricket bat = ` 980
Profit % = 12%

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