Mixture and Alligation MCQs for Competitive Examination
Solve the following problems.
Q. 21
A drum contains 80 litres of ethanol, 20 litres of this liquid is removed and replaced with water. 20 litres of this mixture is again removed and replaced with water. How much of water (in litres) is present in this drum now?
(A) 45 litres
(B) 40 litres
(C) 35 litres
(D) 44 litres
Answer: (C) 35 litres
Explanation: Remaining quantity of ethanol = 80(1 – (20/80))² = 45 litres
Quantity of water = (80 – 45) litres = 35 litres
Q. 22
Solution A contains 10% acid and solution B contains 30% acid. In what ratio should solution A be mixed with solution B to obtain a mixture with 25% acid?
(A) 1 : 2
(B) 3 : 1
(C) 1 : 3
(D) 2 : 1
Answer: (C) 1 : 3
Explanation: N/A
Q. 23
An alloy is made by mixing metal A costing Rs 2000/kg and metal B costing Rs 400/kg in the ratio A : B = 3 : 1. What is the cost (in Rs) of 8 kilograms of this alloy?
(A) 1600
(B) 9800
(C) 6400
(D) 12800
Answer: (D) 12800
Explanation: N/A
Q. 24
In what ratio wheat at Rs 32 per kg should be mixed with wheat at Rs 24 per kg so that on selling the mixture at Rs 39 per kg, there is a profit of 30%?
(A) 3 : 1
(B) 2 : 3
(C) 1 : 4
(D) 2 : 5
Answer: (A) 3 : 1
Explanation: N/A
Q. 25
In two types of brass, the ratios of Copper to Zinc are 8 : 3 and 15 : 7 respectively. If the two types of brass are melted and mixed in the ratio 5 : 2 a new type of brass is obtained. The ratio of Copper to Zinc in this new type of brass is
(A) 3 : 2
(B) 2 : 3
(C) 3 : 4
(D) 5 : 2
Answer: (D) 5 : 2
Explanation: N/A
Q. 26
Gold is 19 times as heavy as water and Copper is 9 times as heavy as water. In what ratio should these be mixed to get an alloy 15 times as heavy as water?
(A) 1 : 1
(B) 1 : 2
(C) 2 : 3
(D) 3 : 2
Answer: (D) 3 : 2
Explanation: N/A
Q. 27
Two blends of a commodity costing Rs 35 and Rs 40 per kg respectively are mixed in the ratio of 2 : 3 by weight. If one-fifth of the mixture is sold at Rs 46 per kg and the remaining part at the rate of Rs 55 per kg, then the profit per cent is
(A) 50
(B) 30
(C) 40
(D) 20
Answer: (C) 40
Explanation: Total amount of mixture = 5 kg (suppose)
Cost Price of 5 kg of mixture = (2 * 35 + 3 * 40)= 190 rs
Selling price of 5 kit of mixture = (1 * 46 + 4 * 55) = 266 rs
Profit = (266-190) = 76 rs
Profit % = (76 * 100)/190 = 40
Q. 28
60 kg of an alloy A is mixed with 100 kg of alloy B. If alloy A has lead and tin in the ratio of 3 : 2 and alloy B has tin and copper in the ratio of 1 : 4, the amount of tin in the new alloy is
(A) 53 kg
(B) 44 kg
(C) 80 kg
(D) 24 kg
Answer: (B) 44 kg
Explanation: Lead and Tin in mixture A is 36 kg and 24 kg respectively
and, Tin and Copper in mixture B is 20 kg and 80 kg
Total amount of Tin in the alloy = (20 + 24) = 44 kg
Q. 29
In a mixture of three varieties of tea, the ratio of their weights is 4 : 5 : 8. If 5 kg tea of the first variety, 10 kg tea of the second variety and some quantity of tea from the third variety are added to the mixture, the ratio of the weights of three varieties of tea becomes 5 : 7 : 9. In the final mixture, the quantity (in kg) of the third variety of tea was
(A)42
(B) 45
(C) 48
(D) 40
Answer: (B) 45
Explanation: Let, Amount of first variety tea = 4x, second variety = 5x, third variety = 8x, and also the quantity of tea from the third variety of tea to be mixed = y
Resultant ratio = (4x + 5) : (5x + 10) : (8x + y) = 5 : 7 : 9
Solving, we have, x = 5, and y = 5 kg
Therefore, the required quantity of third variety of tea = (8 * 5 + 5) = 45 kg
Q. 30
A container has a mixture of two liquids A and B in the ratio 7 : 5. When 9 litres of mixture is drained off and the container is filled with B, the ratio of A and B becomes 7 : 9. How many litres of liquid A was carried by the container initially?
(A) 10 litres
(B) 20 litres
(C) 21 litres
(D) 25 litres
Answer: (C) 21 litres
Explanation: N/A
Q. 31
An alloy contains copper zinc and nickel in the ratio of 5 : 3 : 2. The quantity of nickel (in kg) that must be added to 100 kg of this alloy to have the new ratio 5 : 3 : 3 is
(A) 8
(B) 10
(C) 12
(D) 15
Answer: (B) 10
Explanation: N/A
Q. 32
There are three containers of equal capacity. The ratio of Sulphuric acid to water in the first container is 3 : 2, that in the second container is 7 : 3 and in the third container it is 11 : 4. If all the liquids are mixed together, then the ratio of Sulphuric acid to water in the mixture will be
(A) 61 : 29
(B) 61 : 28
(C) 60 : 29
(D) 59 : 29
Answer: (A) 61 : 29
Explanation: N/A
Q. 33
The ratio of milk and water in mixtures of four containers are 5 : 3, 2 : 1, 3 : 2 and 7 : 4 respectively. In which container is the quantity of milk, relative to water is minimum?
(A) First
(B) Second
(C) Third
(D) Fourth
Answer: (C) Third
Explanation: N/A
Q. 34
In one glass, milk and water are mixed in the ratio 3 : 5 and in another glass, they are mixed in the ratio 6 : 1. In what ratio should the contents of the two glasses be mixed together so that the new mixture contains milk and water in the ratio 1 : 1?
(A) 20 : 7
(B) 8 : 3
(C) 27 : 4
(D) 25 : 9
Answer: (A) 20 : 7
Explanation: N/A
Q. 35
A jar contains a mixture of two liquids A and B in the ratio 4 : 1. When 10 litres of the mixture was taken out and 10 litres of liquid B was poured into the jar, this ratio became 2 : 3. The quantity of liquid A contained in the jar initially was
(A) 4 litres
(B) 8 litres
(C) 16 litres
(D) 40 litres
Answer: (C) 16 litres
Explanation: N/A
Q. 36
A liquid ‘P’ is 1(3/7) times as heavy as water and water is (5/7) times as heavy as another liquid ‘Q’. The amount of liquid ‘P that must be added to 7 litres of the liquid ‘Q’ so that the mixture may weigh as much as an equal volume of water, will be
(A) 7 litres
(B) 5(1/6) litres
(C) 5 litres
(D) 4(2/3) litres
Answer: (D) 4(2/3) litres
Explanation: Let x litres of liquid P is mixed with 7 litres of liquid Q.
According to the question,
(10/7)x + (5/7) * 7 = x + 7
Solving x = 4(2/3)
Q. 37
Vessels A and B contain mixtures of milk and water in the ratios 4 : 5 and 5 : 1 respectively. In what ratio should the quantities of mixture be taken from A and B to form a mixture in which milk to water is in the ratio 5 : 4?
(A) 2 : 5
(B) 4 : 3
(C) 5 : 2
(D) 2 : 3
Answer: (C) 5 : 2
Explanation: N/A
Q. 38
A barrel contains a mixture of wine and water in the ratio 3 : 1. How many fractions of the mixture must be drawn off and substituted by water so that the ratio of wine and water in the resultant mixture in the barrel becomes 1 : 1?
(A) (1/4)
(B) (1/3)
(C) (3/4)
(D) (2/3)
Answer: (B) (1/3)
Explanation: N/A
Q. 39
In 30 litres mixture of acid, the ratio of acid and water is 2 : 3. What amount of water should be added to the mixture so that the ratio of acid and water becomes 2 : 5?
(A) 10 litres
(B) 15 litres
(C) 18 litres
(D) 12 litres
Answer: (D) 12 litres
Explanation: N/A
Q. 40
A mixture contains spirit and water in the ratio of 3 : 2. If it contains 3 litres more spirit than water, the quantity of spirit in the mixture is
(A) 10 litres
(B) 12 litres
(C) 8 litres
(D) 9 litres
Answer: (D) 9 litres
Explanation: N/A