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**Exercise 8.3 **

**Question 1: ****Tell what is the profit or loss in the following transactions. Also find profit percent or loss percent in each case. **

**(a) Gardening shears bought for Rs 250 and sold for Rs 325. **

**(b) A refrigerator bought Rs12,000 and sold at Rs 13,500. **

**(c) A cupboard bought for Rs 2,500 and sold at Rs 3,000. **

**(d) A skirt bought for Rs 250 and sold at Rs 150. **

**Answer 1: ****(a)** Cost price of gardening shears = Rs 250

Selling price of gardening shears = Rs 325

Since, S.P. > C.P., therefore here is profit.

âˆ´ Profit = S.P. - C.P. = Rs 325 - Rs 250 = Rs 75

**(b) **Cost price of refrigerator = Rs 12,000

Selling price of refrigerator = Rs 13,500

Since, S.P. > C.P., therefore here is profit.

âˆ´ Profit = S.P. - C.P. = Rs 13500 - Rs 12000 = Rs 1,500

Therefore, Profit = Rs 1,500 and Profit% = 12.5%

**(c)** Cost price of cupboard = Rs 2,500

Selling price of cupboard = Rs 3,000

Since, S.P. > C.P., therefore here is profit.

âˆ´ Profit = S.P. - CP. = Rs 3,000 - Rs 2,500 = Rs 500

Therefore, Profit = Rs 500 and Profit% = 20%

**(d) **Cost price of skirt = Rs 250

Selling price of skirt = Rs 150

Since, C.P. > S.P., therefore here is loss.

âˆ´ Loss = CP, - S.P. = Rs 250 - Rs 150 = Rs100

Therefore, Profit = Rs 100 and Profit% = 40%

**Question 2: ****Convert each part of the ratio to percentage: **

**(a) 3 : 1 **

**(b) 2 : 3 : 5 **

**(c) 1 : 4 **

**(d) 1 : 2 : 5 **

**Answer 2: ****(a) **3 :1

Total part =3 + 1= 4

Therefore, Fractional part = 3/4 : 1/4

â‡’ Percentage of parts =** **

â‡’ Percentage of parts = 75% : 25%

**(b) **2 : 3 : 5

Total part = 2 + 3 + 5 = 10

Therefore, Fractional part =

â‡’ Percentage of parts

â‡’ Percentage of parts = 20% : 30% : 50%

**(c)** 1:4

Total part =1 + 4 = 5

Therefore, Fractional part = 1/5 : 4/5

â‡’ Percentage of parts

â‡’ Percentage of parts = 20%: 00%

**(d)** 1 : 2 : 5

Total part = 1+ 2 + 5 = 8

Therefore, Fractional part =

â‡’ Percentage o f parts

â‡’ Percentage of parts = 12.5% : 25% : 62.5%

**Question 3: ****The population of a city decreased from 25,000 to 24,500. Find the percentage decrease. **

**Answer 3: **The decreased population of a city from 25,000 to 24,500.

Population decreased = 25,000 - 24,500 = 500

**Decreased Percentage **

Hence, the percentage decreased is 2%.

**Question 4: ****Arun bought a car for Rs 3,50,000. The next year, the price went up to Rs 3,70,000. What was the percentage of price increase? **

**Answer 4: **Increased in price of a car from Rs 3,50,000 to Rs 3,70,000.

Amount change = Rs 3,70,000 - Rs 3,50,000 = Rs 20,000.

Therefore, Increased percentage** = **

Hence, the percentage of price increased is

**Question 5: ****I buy a T.V. for Rs 10,000 and sell it at a profit of 20%. How much money do I get for it? **

**Answer 5: **The cost price of T.V. = Rs 10,000

profit percent = 20% Now,

Profit = Profit% of C.P,

Selling price = C.P. + Profit = Rs 10,000 + Rs 2,000 = Rs 12,000

Hence, he gets Rs 12,000 on selling his T.V.

**Question 6: ****Juhi sells a washing machine for Rs 13,500. She loses 20% in the bargain. What was the price at which she bought it? **

**Answer 6: **Selling price of washing machine = Rs. 13,500

Loss percent = 20%

Let the cost price of washing machine be Rs x.

Since, Loss = Loss% of C.P.

Therefore, S.P. = C.P, - Loss

â‡’

â‡’

â‡’

**Question 7: ****(i) Chalk contains Calcium, Carbon and Oxygen in the ratio 10:3:12. Find the percentage of Carbon in chalk. **

**(ii) If in a stick of chalk, Carbon is 3 g, what is the weight of the chalk stick? **

**Answer 7: ****(i) **Given ratio = 10 : 3 : 12

Total part = 10 + 3 + 12 = 25

Part of Carbon = 3/25

Percentage of Carbon part in chalk =

(ii) Quantity of Carbon in chalk stick = 3 g

Let the weight of chalk be x g.

Then, 12 % of x = 3

Hence, the weight of chalk stick is 25 g.

**Question 8: ****Amina buys a book for Rs 275 and sells it at a loss of 15%. How much does she sell it for? **

**Answer 8: **The cost of a book = Rs 275

Loss percent = 15%

Loss = Loss% of C.P. = 1 5 % of Rs 275

Therefore, S.P. = C.P. - Loss = Rs 275 - Rs 41.25 = Rs 233.75

Hence, Amina sells a book for Rs 233.75,

**Question 9: ****Find the amount to be paid at the end of 3 years in each case: **

**(a) Principal = Rs 1,200 at 12% p.a. **

**(b) Principal = Rs 7,500 at 5% p.a. **

**Answer 9: ****(a) **Here, Principal (P) = Rs 1,200, Rate (R) = 12% p.a., Time (T) = 3 years

Now, Amount = Principal + Simple Interest

= Rs 1200 + Rs 432

= Rs 1,632

(b) Here, Principal (P) = Rs 7,500, Rate (R) = 5% p.a., Time (T) = 3 years

Now, Amount = Principal + Simple Interest

= Rs 7,500 + Rs 1,125

= Rs 8,625

**Question 10: ****What rate gives Rs 280 as interest on a sum of Rs 56,000 in 2 years? **

**Answer 10: **Here, Principal (P) = Rs 56,000, Simple Interest (S.I.) = Rs 280, Time (T) = 2 years

Hence, the rate of interest on sum is 0.25%.

**Question 11: ****If Meena gives an interest of Rs 45 for one year at 9% rate p.a. What is the sum she has borrowed? **

**Answer 11: **Simple Interest = Rs 45, Rate (R) = 9% p.a., Time (T) = 1 years

Hence, she borrowed Rs 500.

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