1. The average of 18 numbers is 42. If the average of 10 numbers is 40, find the average of the remaining numbers.
a) 44
b) 45
c) 46
d) 47
2. A sum amounts to ₹9,600 in 4 years and ₹10,800 in 6 years at simple interest. Find the principal.
a) ₹7,200
b) ₹7,800
c) ₹8,400
d) ₹9,000
3. The ratio of two numbers is 8 : 11 and their difference is 36. Find the larger number.
a) 108
b) 120
c) 132
d) 144
4. A train travels 300 km. If the speed were increased by 20 km/h, the journey would take 1 hour less. Find the original speed.
a) 40 km/h
b) 50 km/h
c) 60 km/h
d) 75 km/h
5. If the cost price of 30 items equals the selling price of 24 items, what is the profit percentage?
a) 20%
b) 25%
c) 30%
d) 35%
6. A number is increased by 30% and then decreased by 10%. What is the net percentage change?
a) 17% increase
b) 20% increase
c) 15% increase
d) 18% increase
7. A bag contains 7 red, 5 blue and 8 green balls. What is the probability of drawing a green ball?
a) ⅖
b) 4/10
c) 3/10
d) 8/20
8. A mixture of milk and water is in the ratio 6 : 5. If 11 litres of water are added, the ratio becomes 6 : 7. Find the original quantity of the mixture.
a) 44 L
b) 55 L
c) 66 L
d) 77 L
9. Two numbers are in the ratio 5 : 8 and their sum is 169. Find the smaller number.
a) 55
b) 60
c) 65
d) 70
10. A boat travels 40 km downstream in 4 hours and the same distance upstream in 5 hours. Find the speed of the stream.
a) 1 km/h
b) 2 km/h
c) 3 km/h
d) 4 km/h
11. The side of a square is increased by 25%. By what percentage does the area increase?
a) 50%
b) 56.25%
c) 60%
d) 62.5%
12. The average of 16 numbers is 24. If four numbers with average 18 are removed, find the average of the remaining numbers.
a) 25
b) 26
c) 27
d) 28
13. A man spends 75% of his income. If his savings are ₹6,000, what is his income?
a) ₹18,000
b) ₹20,000
c) ₹24,000
d) ₹30,000
14. If the radius of a circle increases by 10%, by what percentage does the area increase?
a) 20%
b) 21%
c) 22%
d) 25%
15. The present ages of A and B are in the ratio 6 : 7. After 8 years, the ratio becomes 7 : 8. Find A’s present age.
a) 36
b) 42
c) 48
d) 54
Answers
- Correct Answer: B Total = 18×42 = 756 First 10 = 10×40 = 400 Remaining = 356 Average = 356/8 = 45
- Correct Answer: A Difference = 10800 − 9600 = 1200 (2 yrs interest) 1 yr SI = 600 Principal = 9600 − (4×600) = ₹7200
- Correct Answer: C Difference = 3 parts = 36 1 part = 12 Larger = 11×12 = 132
- Correct Answer: C Let speed = x 300/x − 300/(x+20) = 1 x = 60 km/h
- Correct Answer: B CP of 30 = SP of 24 CP/SP = 24/30 = ⅘ Profit = 25%
- Correct Answer: A 100 × 1.30 = 130 130 × 0.90 = 117 Increase = (130-117) × 100 = 17% increase
- Correct Answer: A Green = 8 Total = 20 Probability = 8/20 = ⅖
- Correct Answer: B Water increase = 2 parts = 11 L 1 part = 5.5 Total parts = 11 Mixture = 11×5 = 55 L
- Correct Answer: C Total parts = 13 1 part = 169/13 = 13 Smaller = 5×13 = 65
- Correct Answer: A Downstream = 40/4 = 10 Upstream = 40/5 = 8 Stream = (10−8)/2 = 1 km/h
- Correct Answer: B Area factor = (1.25)² = 1.5625 Increase = 56.25%
- Correct Answer: B Total = 16×24 = 384 Removed = 4×18 = 72 Remaining = 312 Average = 312/12 = 26
- Correct Answer: C Savings = 25% 25% = 6000 Income = 6000×4 = ₹24,000
- Correct Answer: B Area ∝ r² (1.1)² = 1.21 Increase = 21%
- Correct Answer: C Let ages = 6x, 7 (6x+8)/(7x+8) = ⅞ x = 8 A = 6×8 = 48