Friday, January 3, 2025

Class 8 Maths Solution | Lesson 5 Profit and Loss | Curriculum Development Centre (CDC)

Lesson 5 Profit and LossClass 8 Maths Solution | Lesson 5 Profit and Loss | Curriculum Development Centre (CDC)


Study Note - Unit 1 Example 1

Rajukanta bought a story book of cost Rs. 600 at a discount of 15%. How much amount does he have to pay to the shopkeeper?

Solution

Here, the marked price of story book (MP) = Rs. 600

Discount (D) = 15%

Selling price (SP) = ?

We know that,

Discount amount = 15% of Rs. 600

Selling Price (SP) = MP - Discount amount

= 600 - 90

= Rs. 510

Alternative method

Let the marked price (MP) = 100x

Discount (D) = 15x

Selling price (SP) = 85x

By the question,

MP = Rs. 600

or, 100x = 600

∴ x = 6

85x = 85 x 6

= Rs. 510

Hence, he has to pay Rs. 510 for the story books.

Example 2

If Nabin buys a mobile at 8% discount and has to pay Rs. 22,080 to the shopkeeper, find the marked price of the mobile.

Solution

Here, Discount of mobile = 8%

Selling price (SP) = Rs. 22,080

Marked price (MP) = ?

Let, marked price (MP) = x

We know that,

SP = MP - discount % of MP

or, 22080 = x - 8/100 x

or, 22080 = x - 8x/100

or, 22080 = 100x - 8x/100

or, 22080 = 92x/100

or, x = 22080 x 100/92

Alternative method

Here,

Let, marked price (MP) = 100x

Discount (D) = 8x

Selling price (SP) = MP - discount amount

= 100x - 8x

= 92x

By the question,

SP = Rs. 22,080

or, 92x = 22,080

∴ x = 240

MP = 100x

= 100 x 240

= Rs. 24,000

Hence, the marked price of the mobile is Rs. 24,000.

Example 3

Ujjwal buys a computer at Rs. 36,000. The marked price of the computer is 25% above the cost price. If he sells the computer at a 25% discount then,

(a) What is the marked price of the computer?

(b) What is the discount amount?

(c) What is the selling price of the computer?

(d) What is his profit or loss percent from that computer? Find it.

Solution

Here, cost price of computer (CP) = Rs. 36,000

By the question,

(a) Marked price (MP) = ?

Marked price (MP) = CP + 25% of CP

= 36000 + 36000 x 25/100

= 36000 + 9000

= Rs. 45,000

(b) Discount = ?

We know that,

Discount = discount % of MP

= 45000 x 25/100

= Rs. 11,250

(c) Selling price (SP) = ?

By formula,

SP = MP - Discount

= 45000 - 11250

= Rs. 33,750

(d) Profit or Loss percent = ?

Since the selling price of the computer is less than the cost price, there is a loss.

Loss = CP - SP

= 36,000 - 33,750

= Rs. 2,250

Loss percent = (Loss / CP) x 100

= 2250 / 36000 x 100

= 6.25%

Exercise 5.1

1. The following are the calculations to find the selling price (SP) for each item based on the given marked price (MP) and discount amount.

a. Books:

Marked Price (MP) = Rs 480

Discount = Rs 48

SP = MP - Discount

= 480 - 48

= Rs 432

b. Shoes:

Marked Price (MP) = Rs 1250

Discount = Rs 250

SP = MP - Discount

= 1250 - 250

= Rs 1000

c. Calculator:

Marked Price (MP) = Rs 750

Discount = Rs 50

SP = MP - Discount

= 750 - 50

= Rs 700

d. Shirt:

Marked Price (MP) = Rs 1500

Discount = Rs 300

SP = MP - Discount

= 1500 - 300

= Rs 1200

e. Mobile:

Marked Price (MP) = Rs 24500

Discount = Rs 480

SP = MP - Discount

= 24500 - 480

= Rs 240

2. The table below shows the marked price (MP) and selling price (SP) of different items. Calculate the discount amount and discount percentage for each item.

a. Watch:

Marked Price (MP) = Rs 2200

Discount = 15%

SP = MP - (Discount% of MP)

= 2200 - (15/100 × 2200)

= 2200 - 330

= Rs 1870

b. Bag:

Marked Price (MP) = Rs 1750

Discount = 12%

SP = MP - (Discount% of MP)

= 1750 - (12/100 × 1750)

= 1750 - 210

= Rs 1540

c. Cupboard:

Marked Price (MP) = Rs 30000

Discount = 25%

SP = MP - (Discount% of MP)

= 30000 - (25/100 × 30000)

= 30000 - 7500

= Rs 22500

d. Computer:

Marked Price (MP) = Rs 40000

Discount = 10%

SP = MP - (Discount% of MP)

= 40000 - (10/100 × 40000)

= 40000 - 4000

= Rs 36000

e. TV:

Marked Price (MP) = Rs 54500

Discount = 20%

SP = MP - (Discount% of MP)

= 54500 - (20/100 × 54500)

= 54500 - 10900

= Rs 43600

3. The following are the calculations to find the Marked Price (MP) for each item based on the given Selling Price (SP) and Discount Percentage (%).

a. Table:

Selling Price (SP) = Rs 2150

Discount % = 14%

Marked Price (MP) = SP / (1 - Discount % / 100)

= 2150 / (1 - 14 / 100)

= 2150 / 0.86

= Rs 2500

b. Sari:

Selling Price (SP) = Rs 1360

Discount % = 20%

Marked Price (MP) = SP / (1 - Discount % / 100)

= 1360 / (1 - 20 / 100)

= 1360 / 0.80

= Rs 1700

c. Coat:

Selling Price (SP) = Rs 4100

Discount % = 18%

Marked Price (MP) = SP / (1 - Discount % / 100)

= 4100 / (1 - 18 / 100)

= 4100 / 0.82

= Rs 5000

d. Computer:

Selling Price (SP) = Rs 28800

Discount % = 10%

Marked Price (MP) = SP / (1 - Discount % / 100)

= 28800 / (1 - 10 / 100)

= 28800 / 0.90

= Rs 32000

e. Laptop:

Selling Price (SP) = Rs 80750

Discount % = 5%

Marked Price (MP) = SP / (1 - Discount % / 100)

= 80750 / (1 - 5 / 100)

= 80750 / 0.95

= Rs 85000

4. The following are the calculations to find the selling price (SP) for each item based on the given marked price (MP) and discount percentage.

a. Iron:

Marked Price (MP) = Rs 1800

Discount = 15%

SP = MP - (Discount% of MP)

= 1800 - (15/100 × 1800)

= 1800 - 270

= Rs 1530

b. Telephone set:

Marked Price (MP) = Rs 2500

Discount = 12%

SP = MP - (Discount% of MP)

= 2500 - (12/100 × 2500)

= 2500 - 300

= Rs 2200

c. Motorcycle:

Marked Price (MP) = Rs 245000

Discount = 15%

SP = MP - (Discount% of MP)

= 245000 - (15/100 × 245000)

= 245000 - 36750

= Rs 208250

d. Watch:

Marked Price (MP) = Rs 3000

Discount = 10%

SP = MP - (Discount% of MP)

= 3000 - (10/100 × 3000)

= 3000 - 300

= Rs 2700

e. Printer:

Marked Price (MP) = Rs 30000

Discount = 13%

SP = MP - (Discount% of MP)

= 30000 - (13/100 × 30000)

= 30000 - 3900

= Rs 26100

5. (a) The marked price of a book is Rs. 250. What is the price of the book after a 12% discount?

Solution:

Here, the marked price of the book (MP) = Rs. 250

Discount (D) = 12%

Selling price (SP) = ?

We know that,

Discount amount = 12% of Rs. 250

= 12x250/100

= 30

Selling Price (SP) = MP - Discount amount

= 250 - 30

= Rs. 220

(b) The marked price of a jacket is Rs. 2,250. What is the price of the jacket if the shopkeeper sells it after an 8% discount?

Solution:

Here, the marked price of the jacket (MP) = Rs. 2,250

Discount (D) = 8%

Selling price (SP) = ?

We know that,

Discount amount = 8% of Rs. 2,250

Selling Price (SP) = MP - Discount amount

= 2,250 - 180

= Rs. 2,070

6. (a) If the price of a colour television after 10% discount is Rs. 13,950. What is the marked price of television?

Solution:

Here, the selling price of the television (SP) = Rs. 13,950

Discount (D) = 10%

Marked price (MP) = ?

We know that,

SP = MP - Discount amount

Discount amount = 10% of MP

So, 13,950 = MP - (10% of MP)

13,950 = MP - 0.10 x MP

13,950 = 0.90 x MP

MP = 13,950 / 0.90

MP = Rs. 15,500

(b) If the price of a sweater after 14% discount is Rs. 1,075. What is the marked price of sweater?

Solution:

Here, the selling price of the sweater (SP) = Rs. 1,075

Discount (D) = 14%

Marked price (MP) = ?

We know that,

SP = MP - Discount amount

Discount amount = 14% of MP

So, 1,075 = MP - (14% of MP)

1,075 = MP - 0.14 x MP

1,075 = 0.86 x MP

MP = 1,075 / 0.86

MP = Rs. 1,250

7. A shopkeeper bought a torchlight for Rs. 1,400. The marked price of the torch is 40% above the cost price. If the shopkeeper sold the torch after 20% discount, then

Solution:

Here, the cost price (CP) of the torch = Rs. 1,400

Marked price (MP) = 40% above the cost price

MP = CP + 40% of CP

MP = 1,400 + (40/100) x 1,400

MP = 1,400 + 560

MP = Rs. 1,960

(a) What is the marked price of the torchlight?

The marked price of the torchlight = Rs. 1,960

(b) What is the discount amount for the customer?

Discount amount = 20% of Rs. 1,960

Discount amount = (20/100) x 1,960 = Rs. 392

(c) What is the selling price of the torch?

Selling price (SP) = MP - Discount amount

SP = 1,960 - 392

SP = Rs. 1,568

(d) What is the profit of the shopkeeper after selling the torch?

Profit = Selling price (SP) - Cost price (CP)

Profit = 1,568 - 1,400

Profit = Rs. 168

8. The cost price of a mobile is Rs. 21,000. The marked price of the mobile is 30% above the cost price. If the shopkeeper sold the mobile after a 20% discount then,

Solution:

Here, the cost price (CP) of the mobile = Rs. 21,000

Marked price (MP) = 30% above the cost price

MP = CP + 30% of CP

MP = 21,000 + (30/100) x 21,000

MP = 21,000 + 6,300

MP = Rs. 27,300

(a) What is the marked price of the mobile?

The marked price of the mobile = Rs. 27,300

(b) What is the discount amount for the customer?

Discount amount = 20% of Rs. 27,300

Discount amount = (20/100) x 27,300 = Rs. 5,460

(c) What is the selling price of the mobile?

Selling price (SP) = MP - Discount amount

SP = 27,300 - 5,460

SP = Rs. 21,840

(d) What is the profit of the shopkeeper after selling the mobile?

Profit = Selling price (SP) - Cost price (CP)

Profit = 21,840 - 21,000

Profit = Rs. 840

9. Ramhari bought a computer for Rs. 45,000. The marked price of the computer is 30% above the cost price. If Ramhari sold the computer after a 30% discount then,

Solution:

Here, the cost price (CP) of the computer = Rs. 45,000

Marked price (MP) = 30% above the cost price

MP = CP + 30% of CP

MP = 45,000 + (30/100) x 45,000

MP = 45,000 + 13,500

MP = Rs. 58,500

(a) What is the marked price of the computer?

The marked price of the computer = Rs. 58,500

(b) What is the discount amount?

Discount amount = 30% of Rs. 58,500

Discount amount = (30/100) x 58,500 = Rs. 17,550

(c) What is the selling price of the computer?

Selling price (SP) = MP - Discount amount

SP = 58,500 - 17,550

SP = Rs. 40,950

(d) What is his profit or loss with that computer?

Profit = Selling price (SP) - Cost price (CP)

Profit = 40,950 - 45,000

Profit = -Rs. 4,050 (Loss)

10. Rahaman marks the price of a suitcase as Rs. 6,000. If 15% discount is allowed on the suitcase, he got Rs. 500 profit, then,

Solution:

Here, the marked price (MP) of the suitcase = Rs. 6,000

Discount (D) = 15%

Profit = Rs. 500

(a) What is the discount amount?

Discount amount = 15% of Rs. 6,000

Discount amount = (15/100) x 6,000 = Rs. 900

(b) What is the selling price of the suitcase?

Selling price (SP) = MP - Discount amount

SP = 6,000 - 900

SP = Rs. 5,100

(c) What was the cost price of the suitcase for Rahaman?

Cost price (CP) = Selling price (SP) - Profit

CP = 5,100 - 500

CP = Rs. 4,600

(d) What was his profit percent from the suitcase?

Profit percent = (Profit / Cost price) x 100

Profit percent = (500 / 4,600) x 100

Profit percent = 10.87%

No comments:

Post a Comment

Note: Only a member of this blog may post a comment.

close