Page 119 - Maths Skills - 8

Comparing Quantities 117

Let’s Attempt

Example 1: The marked price of a ceiling fan is ` 825. During off season, it is sold for ` 740. Find the discount
per cent.
Solution: Given: M.P. = ` 825, S.P. = ` 740
Discount = M.P. – S.P. = ` (825 – 740) = ` 85

Discount 85
Discount % = × 100 = × 100 = 10.30%
M.P. 825

∴ Discount % = 10.30%

Example 2: A shopkeeper allows a discount of 10% on an article and still makes a profit of 25%. What does he
pay for an article whose marked price is ` 900?
Solution: Given: M.P. = ` 900 Fact-o-meter
10
Discount = 10% of ` 900 = × ` 900 = ` 90 100 ×S.P.
100 C.P. = 100 +Profit %
∴ S.P. = M.P. – Discount = ` (900 – 90) = ` 810
Profit = 25%

100 S.P. 100 810 100 810
C.P. = = ` 100 = ` = ` 648
100 Profit% 25 125
∴ He pays ` 648 for that article.

Example 3: Calculate the selling price of an article, if its marked price is ` 550 and discount allowed is 10%.
Solution: Given: M.P. = ` 550 and Discount = 10%
We know that discount is always calculated on the marked price.

10
∴ 10% of ` 550 = × ` 550 = ` 55
100
S.P. = M.P. – Discount = ` (550 – 55) = ` 495.

Example 4: Calculate the marked price of an article if it is sold for ` 2660 at a discount of 5%.
Solution: Let the M.P. be ` 100. When S.P. is ` 95, M.P. is ` 100

5
5% of ` 100 = × ` 100 = ` 5 100
100 When S.P. is ` 2660, M.P. is ` 95 2660

S.P. = M.P. – Discount = ` (100 – 5) = ` 95 = ` 2800.

Example 5: Find the single discount equivalent to two successive discounts of 30% and 10%.
Solution: Let the marked price of an article be ` 100.
Price after the first discount of 30% = ` (100 – 30) = ` 70
10
Now, 10% of ` 70 = × ` 70 = ` 7
100
Price after the second discount of 10% = ` (70 – 7) = ` 63
∴ Net S.P. = ` 63
∴ The single discount equivalent to the given discount = (100 – 63)% = 37%.