Chapter-4 (Currency And Exchange Rate) Exercise Solutions

Exercise 4: Questions and Complete Solutions

Mathematics • Grade 10 • Currency and Exchange Rate

Rule used: Foreign → NPR uses the buying rate; NPR → Foreign uses the selling rate. Rates are from the NRB table of Bhadra 5, 2079.

Exercise 4: Questions and Complete Solutions

1. a) What is meant by money exchange?
b) Which of the buying rate or selling rate does a Nepali student use to exchange Nepali Rupees into American Dollars while going abroad to study in America?

a) Changing the currency of one country into the currency of another at a fixed rate is money exchange.

b) The student buys dollars from the bank, so the bank's selling rate is used.

2. By using the buying rate, change the following currencies into Nepali currency: a) Indian Rupees 1425 b) American Dollar 2000 c) Pound Sterling 4672 d) Australian Dollar 672 e) Saudi Riyal 1851 f) Qatari Riyal 2225 g) South Korean Won 58,230 h) Hongkong Dollar 4512 i) Malaysian Ringgit 6725 j) Chinese Yuan 3450

a) 1,425 × 1.60 (IC 100 = Rs. 160) = Rs. 2,280

b) 2,000 × 127.35 = Rs. 2,54,700

c) 4,672 × 150.94 = Rs. 7,05,191.68 (book's 7,04,724.48 uses 150.84)

d) 672 × 87.82 = Rs. 59,015.04

e) 1,851 × 33.91 = Rs. 62,767.41

f) 2,225 × 34.82 = Rs. 77,474.50

g) 100 Won = Rs. 9.58, so 58,230 × 9.58 ÷ 100 = Rs. 5,578.43

h) 4,512 × 16.23 = Rs. 73,229.76

i) 6,725 × 28.45 = Rs. 1,91,326.25

j) 3,450 × 18.70 = Rs. 64,515

3. By using the selling rate, change Rs. 2,00,000 into: a) Australian Dollar b) American Dollar c) Euro d) United Arab Emirates Dirham

a) 2,00,000 ÷ 88.23 = A$ 2,266.80

b) 2,00,000 ÷ 127.95 = $1,563.11

c) 2,00,000 ÷ 128.73 = €1,553.63

d) 2,00,000 ÷ 34.83 = 5,742.17 Dirham (34.83 as in the answer key)

4. On a specific day, the buying and selling rates for 1 American Dollar are Rs. 127.50 and Rs. 128 respectively.
a) How many American Dollars can be exchanged for Rs. 81,280?
b) How many Nepali Rupees can you exchange with American Dollar 600?

a) Rupees → dollars uses the selling rate: 81,280 ÷ 128 = $635

b) Dollars → rupees uses the buying rate: 600 × 127.50 = Rs. 76,500

5. On 23 August 2022, the buying and selling rates for Chinese Yuan 1 are Rs. 18.64 and Rs. 18.73 respectively.
a) How many Chinese Yuan can be exchanged for Rs. 37,460?
b) How many Nepalese rupees can you exchange with Chinese Yuan 5000?

a) 37,460 ÷ 18.73 = 2,000 Yuan

b) 5,000 × 18.64 = Rs. 93,200

6. Using the above table, answer:
a) How many UAE Dirhams are equal to 1 Euro?
b) How many Malaysian Ringgits are equal to 1 Qatari Riyal?
c) How many Canadian Dollars are equal to 200 American Dollars?
d) How many Thai Baht are equal to 200 Pound Sterling?

a) 1 Euro = Rs. 128.13; 1 Dirham = Rs. 34.83. 128.13 ÷ 34.83 = 3.68 Dirham

b) 1 Qatari Riyal = Rs. 34.82; 1 Ringgit = Rs. 28.58. 34.82 ÷ 28.58 = 1.22 Ringgit

c) 200 × 127.35 = Rs. 25,470; ÷ 98.54 = 258.47 CAD

d) 200 × 150.94 = Rs. 30,188; ÷ 3.59 = 8,408.91 Baht

7. Sobita went to Australia for higher studies and now works as a secondary level teacher. She earns 37 Australian Dollars per hour and teaches 5 hours a day except Sunday. If A$1 = Rs. 90:
a) How much salary does she have in Nepali Rupees for a week?
b) Find her monthly salary in Nepali Rupees.

Per day = 37 × 5 = A$185. Teaching days per week = 6.

a) Weekly = 185 × 6 = A$1,110; 1,110 × 90 = Rs. 99,900

b) Month = 30 days = 5 weeks: 99,900 × 5 = Rs. 4,99,500

8. a) An American businessman exchanged American Dollars for NRs. 12,40,000 at $1 = NRs. 124. After a week, Nepali currency is inflated by 10%. He then exchanged the dollars into Nepali currency. Find his loss or profit.
b) A businessman exchanged Nepali currency Rs. 7,20,000 at 1 Thai Baht = NRs. 3.60 to buy goods from Thailand. After a day Nepali currency is deflated by 5%. He cancels the purchase and exchanges the Baht back into Nepali currency. Find his loss or profit.

a) Dollars = 12,40,000 ÷ 124 = $10,000. New rate = 124 + 10% of 124 = Rs. 136.40. Rupees = 10,000 × 136.40 = Rs. 13,64,000. Profit = 13,64,000 − 12,40,000 = Rs. 1,24,000

b) Baht = 7,20,000 ÷ 3.60 = 2,00,000. New rate = 3.60 − 5% of 3.60 = Rs. 3.42. Rupees = 2,00,000 × 3.42 = Rs. 6,84,000. Loss = 7,20,000 − 6,84,000 = Rs. 36,000

9. a) A Nepali visiting the UAE bought a 75 inch branded television for 10,000 Dirham. The rate that day was 1 Dirham = NRs. 34.50. He paid 20% custom tax and 13% VAT. His relative wishes to buy it. At what price should he sell it to break even?
b) A good sold for Indian rupees 21,600 gains 20% profit. At what Nepalese rupee price can it be sold to gain 25% profit?

a) Cost = 10,000 × 34.50 = Rs. 3,45,000. Custom 20% = Rs. 69,000, so total = 4,14,000. VAT 13% of 4,14,000 = Rs. 53,820. Break-even price = 4,14,000 + 53,820 = Rs. 4,67,820

b) 120% of CP = IC 21,600 ⇒ CP = 21,600 × 100 ÷ 120 = IC 18,000. SP at 25% profit = 18,000 × 125/100 = IC 22,500. In NPR = 22,500 × 1.60 = Rs. 36,000

10. a) A Nepali doing business in Australia wished to take 500 Pashmina shawls back with him. He bought them at Rs. 3,500 each and took them to Australia paying 5% export tax. He paid A$30 for transport from the airport to his residence, and sold the shawls at A$80 each. Find his profit or loss percent. (A$1 = NRs. 88.50)
b) The air ticket fare from Kathmandu to Bangkok of Nepal Airlines is Rs. 28,000. The same ticket can be bought for 8000 Thai Baht in Thailand. By what percent is it cheaper to buy from which place? (1 Baht = NRs. 3.50)

a) Cost of shawls = 500 × 3,500 = Rs. 17,50,000. Export tax 5% = Rs. 87,500, so 18,37,500. Transport = 30 × 88.50 = Rs. 2,655. Total CP = Rs. 18,40,155.

SP = 500 × 80 = A$40,000 = 40,000 × 88.50 = Rs. 35,40,000. Profit = 35,40,000 − 18,40,155 = Rs. 16,99,845.

Profit % = 16,99,845 ÷ 18,40,155 × 100 = 92.37%

b) As printed, 8,000 × 3.50 = Rs. 28,000, the same as Kathmandu. The answer key (6.97%) works with 8,600 Baht: 8,600 × 3.50 = Rs. 30,100. Difference = 30,100 − 28,000 = Rs. 2,100. Percent = 2,100 ÷ 30,100 × 100 = 6.97% cheaper in Kathmandu

11. a) If American Dollar 176 = 100 Pound Sterling and £1 = Nepali Rupees 151, how many Nepali Rupees can be exchanged for 132 American Dollars?
b) If IC 100 = NRs. 160 and 1 American Dollar = NRs. 120, how many American Dollars are equal to IC 7,500?
c) If Chinese Yuan 1 = NRs. 18.70 and UAE Riyal 1 = NRs. 33.91, change Chinese Yuan 5612 into UAE Riyal.

a) Let Rs. x = $132. Chain: $176 = £100; £1 = Rs. 151; Rs. x = $132. Then 176 × 1 × x = 100 × 151 × 132, so x = 19,93,200 ÷ 176 = Rs. 11,325

b) IC 7,500 = 7,500 × 160 ÷ 100 = Rs. 12,000. Dollars = 12,000 ÷ 120 = $100

c) 5,612 Yuan = 5,612 × 18.70 = Rs. 1,04,944.40. Riyal = 1,04,944.40 ÷ 33.91 = 3,094.79 Riyal

Currency and Exchange Rate • Grade 10 Mathematics