Mixtures And Allegations(Quantitative Aptitude ) Questions and answers for exam Preparation

Quantitative Aptitude

MIXTURES AND ALLEGATIONS MCQs

Alligations And Mixtures

Total Questions : 245 | Page 2 of 25 pages

Question 11. A container contains 40 litres of milk. From this container 4 litres of milk was taken out and replaced by water. This process was repeated further two times. How much milk is now contained by the container?

26.34 litres
27.36 litres
28 litres
29.16 litres

Discuss Question

Answer: Option D. -> 29.16 litres
Answer: (d).29.16 litres

Question 12. A dishonest milkman professes to sell his milk at cost price but he mixes it with water and thereby gains 25%. The percentage of water in the mixture is:

Discuss Question

Answer: Option C. -> 20%
Answer: (c).20%

Question 13. How many kilogram of sugar costing Rs. 9 per kg must be mixed with 27 kg of sugar costing Rs. 7 per kg so that there may be a gain of 10% by selling the mixture at Rs. 9.24 per kg?

36 kg
42 kg
54 kg
63 kg

Discuss Question

Answer: Option D. -> 63 kg
Answer: (d).63 kg

Question 14. In what ratio must water be mixed with milk to gain 16(2/3)% on selling the mixture at cost price?

1 : 6
6 : 1
2 : 3
4 : 3

Discuss Question

Answer: Option A. -> 1 : 6
Answer: (a).1 : 6

Question 15. A jar full of whisky contains 40% alcohol. A part of this whisky is replaced by another containing 19% alcohol and now the percentage of alcohol was found to be 26%. The quantity of whisky replaced is:

Discuss Question

Answer: Option B. -> 2/3
Answer: (b).2/3

Question 16.

Find the ratio in which rice at Rs. 7.20 a kg be mixed with rice at Rs. 5.70 a kg to produce a mixture worth Rs. 6.30 a kg.

1 : 3
2 : 3
3 : 4
4 : 5

Discuss Question

Answer: Option B. -> 2 : 3

By the rule of alligation:

Cost of 1 kg of 1^st kind
Cost of 1 kg of 2^nd kind
720 p
Mean Price
630 p
570 p
60
90

Required ratio = 60 : 90 = 2 : 3.

Question 17.

In what ratio must a grocer mix two varieties of tea worth Rs. 60 a kg and Rs. 65 a kg so that by selling the mixture at Rs. 68.20 a kg he may gain 10%?

3 : 2
3 : 4
3 : 5
4 : 5

Discuss Question

Answer: Option A. -> 3 : 2

S.P. of 1 kg of the mixture = Rs. 68.20, Gain = 10%.

C.P. of 1 kg of the mixture = Rs.

100
x 68.20

= Rs. 62.
110

By the rule of alligation, we have:

Cost of 1 kg tea of 1^st kind.
Cost of 1 kg tea of 2^nd kind.
Rs. 60
Mean Price
Rs. 62
Rs. 65
3
2

Required ratio = 3 : 2.

Question 18.

The cost of Type 1 rice is Rs. 15 per kg and Type 2 rice is Rs. 20 per kg. If both Type 1 and Type 2 are mixed in the ratio of 2 : 3, then the price per kg of the mixed variety of rice is:

Rs. 18
Rs. 18.50
Rs. 19
Rs. 19.50

Discuss Question

Answer: Option A. -> Rs. 18

Let the price of the mixed variety be Rs. x per kg.

By rule of alligation, we have:

Cost of 1 kg of Type 1 rice
Cost of 1 kg of Type 2 rice
Rs. 15
Mean Price
Rs. x
Rs. 20
(20 - x)
(x - 15)

(20 - x)
=
2
(x - 15)
3

60 - 3x = 2x - 30

5x = 90

x = 18.

Question 19.

8 litres are drawn from a cask full of wine and is then filled with water. This operation is performed three more times. The ratio of the quantity of wine now left in cask to that of water is 16 : 65. How much wine did the cask hold originally?

18 litres
24 litres
32 litres
42 litres

Discuss Question

Answer: Option B. -> 24 litres

Let the quantity of the wine in the cask originally be x litres.

Then, quantity of wine left in cask after 4 operations =

x

1 -
8

4
litres.
x

x(1 - (8/x))⁴

=
16
x
81

1 -
8

4
=

2

4
x
3

x - 8

=
2
x
3

3x - 24 = 2x

x = 24.

Question 20.

A merchant has 1000 kg of sugar, part of which he sells at 8% profit and the rest at 18% profit. He gains 14% on the whole. The quantity sold at 18% profit is: