MIXTURE AND ALLIGATION (QUANTITATIVE APTITUDE) EPFO UPSC

Total Questions: 30

1. Alcohol cost ₹ 3.50 per litre and kerosene oil cost ₹ 2.50 per litre. In what proportion these should be mixed so that the resulting mixture may be ₹ 2.75 per litre?

Correct Answer: (b) 1 : 3
Solution:

2. Pure milk costs ₹ 3.60 per litre. A milkman adds water to 25 litres of pure milk and sells the mixture at ₹ 3 per litre. How many litres of water does he add?

Correct Answer: (b) 5 litres
Solution:

3. In what ratio must water be mixed with milk to gain 20% by selling the mixture at cost price?

Correct Answer: (b) 1 : 5
Solution:

4. In what ratio must water be mixed with milk to gain 16 2/3% on selling the mixture at cost price?

Correct Answer: (a) 1 : 6 
Solution:

5. The ratio of milk and water in 55 litres of adulterated milk is 7 : 4. How much water must be added to make the mixture’s ratio 7 : 6?

Correct Answer: (b) 10
Solution:

6. How many litres of pure alcohol must be added to 10 litres of mixture which is 15% alcohol to make a mixture which will be 25% alcohol?

Correct Answer: (d) 4/3
Solution:

7. 300 gm of sugar solution has 40% sugar in it. How much sugar should be added to make it 50% in the solution?

Correct Answer: (c) 60 gm
Solution:

8. Gold is 19 times as heavy as water and copper 9 times. In what ratio should these metals be mixed so that the mixture may be 15 times as heavy as water?

Correct Answer: (b) 3 : 2
Solution:

9. In a mixture of 60 litres, the ratio of milk to water is 2 : 1. If the ratio of milk to water is to be 1 : 2, then amount of water (in litres) to be further added is ________.

Correct Answer: (c) 60
Solution:


Ratio of mixture to water = 1 : 1
Therefore, if there is 60 litres of solution, 60 litres of
water should be added.

10. In what ratio must tea at ₹ 62 per kg be mixed with tea at ₹ 72 per kg so that the mixture must be worth ₹ 64.50 per kg?

Correct Answer: (a) 3 : 1 
Solution: