ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 7 Percentage Ex 7.3
Question 1.
Find the discount and the selling price, when:
(i) the marked price = ₹575, discount = 12%
(ii) the printed price = ₹12750, discount = \(8 \frac{1}{3}\)%
Solution:
(i) Marked price = ₹575,
discount = 12%
∴ Amount of discount = 12% of Rs. 575
Net Sale Price = M.P. – discount
= ₹575 – ₹69 = ₹506
(ii) Marked price = Rs. 12750,
Net sale price = M.P. – discount
= ₹12750 – ₹1062·50
= ₹11687·50
Question 2.
Find the discount and the discount percentage, when:
(i) marked price = ₹780, selling price = ₹721·50
(ii) advertised price = ₹28500, selling price = ₹24510
Solution:
(i) Marked price = ₹780,
Selling price = ₹721·50
Discount = M.P. – selling price
= ₹780 – ₹721·50 = ₹58·50
(ii) Advertised price = ₹28500,
selling price = ₹24510
Discount = advertised price – selling price
= ₹28500 – ₹24510 = ₹3990.
Question 3.
A notebook is marked at ₹30. Find the price a student pays for a dozen notebooks if he gets 15% discount.
Solution:
Marked price of one notebook = ₹30
Marked price for one dozen notebook
= ₹30 × 12 = ₹360
Discount = 15%
Amount of discount = 15% of M.P.
Hence the student pays = ₹360 – ₹54 = ₹306
Question 4.
A dealer gave 9% discount on an electric fan and charges ₹ 728 from the customer. Find the marked price of the fan.
Solution:
Let the marked price of the fan = ₹ x
Discount = 9%
amount of discount = 9% of ₹ x
Hence marked the price of the fan = ₹800
Question 5.
The list price of an article is ₹800 and a dealer is selling it at a discount of 20%. Find:
(i) the selling price of the article.
(ii) the cost price of the article if he makes 25% profit on selling it.
Solution:
(i) M.P. = ₹800, discount = 20%
Question 6.
A shopkeeper marks his goods at such a price that would give him a profit of 10% after allowing a discount of 12%. If an article is marked at ₹2250, find its:
(i) selling price
(ii) cost price.
Solution:
(i) Marked price of an article = ₹2250
discount = 12%, S.P. = ?
Hence the cost price = ₹1800
Question 7.
A shopkeeper purchased a calculator for ₹650. He sells it at a discount of 20% and still makes a profit of 20%. Find :
(i) the selling price
(ii) marked price
Solution:
(i) C.P. = ₹650, Profit = 20%, S.P. = ?
Hence the seeling price of the calculator = ₹780.
(ii) S.P. = ₹780, discount = 20%, M.P. = ?
Hence the marked price of calculator = ₹975
Question 8.
A shopkeeper buys a dinner set for ₹ 1200 and marks it 80% above the cost price. If he gives 15% discount on it, find :
(i) the marked price
(ii) the selling price
(iii) his profit percentage.
Solution:
(i) C.P. of a dinner set = ₹1200
Marked price
= ₹1200 + 80% of (₹1200)
= ₹[1200 + \(\frac{80}{100}\) × 12]
= ₹[1200 + 80 × 12]
= ₹[1200 + 960] = ₹2160
(ii) M.P. = ₹2160, discount = 15%,
S.P. = ?
S.P. = \(\left(1-\frac{d}{100}\right)\) of M.P.
Question 9.
The cost price of an article is ₹1600, which is 20% below the marked price. If the article is sold at a discount of 16%, find :
(i) the marked price
(ii) the selling price
(iii) profit percentage.
Solution:
(i) C.P. = ₹1600
Since the cost price of an article is 20% below the marked price
Let the marked price of an article = ₹x
∴ Cost price = Marked price – 20% of Marked price
⇒ ₹ 1600 = x – 20% of x
⇒ ₹1600 = x – \(\frac{20}{100}\) × x
⇒ ₹1600 = \(\frac{80x}{100}\)
⇒ x = ₹1600 × \(\frac{100}{80}\)
= ₹20 × 100 = ₹2000
Hence the marked price of an article = ₹2000
(ii) M.P. of ₹2000, discount = 16%,
S.P. = ?
Question 10.
A shopkeeper allows 20% discount on his goods and still earns a profit of 20%. If an article is sold for ₹360, find:
(i) the marked price
(ii) tine cost price.
Solution:
(i) Since the dealer allows a discount of 20%
(ii) Let the cost price of the article be ₹ x
and Profit is 20%
Hence, the cost price of the article = ₹300
Question 11.
The printed price of a refrigerator is ₹28600. A dealer allows two successive discount of 10% and 5%. Find the price which a customer has to pay for the refrigerator.
Solution:
The printed price of refrigerator = ₹28600
Hence the customer has to pay for the refrigerator = ₹24453.
Question 12.
Two dealers have marked an article at the same price. The first dealer allows two successive discounts of 15% and 5%. The other allows for a discount of 20% which is the better offer?
Solution:
Let the marked price of an article = ₹x
For the first dealer
Hence a 20% discount is better to offer.
Question 13.
Find a single discount equivalent to two successive discounts of 30% and 10%.
Solution:
Let the market price of an article be ₹ x
and a single discount of d% be equivalent to giving
successive discounts of 30% and 10%, then
Hence the single discount of 37% is
equivalent to two given successive discounts.