Question: 21 -

Smith started a business with initial investment of 500000. He incurred a loss of 2% in the first year and in the second year he gained the profit of 10%. Calculate his net profit earned.

Options:

40000

41000

38000

39000

Answer:

39000

Solution:

Initial investment = 500000
Profit = 500000 (1 – 2/100)(1 + 10/100) = 500000 (49/50)(11/10) = 539000
⇒ Net profit earned = 500000 – 539000 = 39000.

---

Question: 22 -

Two years ago the population of a village was 4000. If the annual increase during the two successive years be at the rate of 2% & 4%, find the present population.

Options:

7000

7072

7074

7080

Answer:

7072

Solution:

Present population = 4000 (1 + 2/100)(1 + 4/100) = 4000 (51/50)(26/25) = 7072.

---

Question: 23 -

A company increased the production of cars from 15625 in 2002 to 27000 in 2005. Find the annual rate of growth of production of the cars.

Options:

10%

2%

20%

15%

Answer:

20%

Solution:

Let the annual rate of growth be R% per annum. Then,
⇒ 27000 = 15625 (1 + R/100)3
⇒ 27000/15625 = (1 + R/100)3
⇒ (30/25)3 = (1 + R/100)3
⇒ 30/25 = 1 + R/100
⇒ 1/5 = R/100
⇒ R = 20%.

---

Question: 24 -

Ajay opened a cafe with an initial investment of Rs. 64000. In the first year he incurred the loss of 10%. During second year he gained the profit of 4% and in the third year he gained the profit of 15%. Calculate his net profit gained in the entire three years.

Options:

68889.61

4889.6

68889.5

68889.60

Answer:

4889.6

Solution:

Initial investment = Rs. 64000
Loss in first year = 10%
Profit in second year = 4%
Profit in third year = 15%
profit = 64000 (1 – 10/100)(1 + 4/100)(1 + 15/100) = 64000 (9/10)(26/25)(23/20) = 68889.60.
Net profit = 68889.60 – 64000 = 4889.6.

---

Question: 25 -

900 workers were employed to construct a dam in four years. At the end of first year, 5% workers were retrenched. At the end of the second year 2% of the workers were retrenched. To complete the construction in time, the number of workers were increased to 10% at the end of third year. How many workers were working at the end of fourth year.

Options:

1000

921

989

945

Answer:

921

Solution:

Initial number of workers = 900
Reduction of workers at the end of first year = 5%
Reduction of workers at the end of second year = 2%
Increase of workers at the end third year = 10%
Number of workers working during fourth year = 900 (1 – 5/100)(1 – 2/100)(1 + 10/100)
= 900 (95/100)(98/100)(110/100) = 921.69 ≅ 921 workers.

---