SBI Clerk Prelims 2016- Practice Aptitude Questions (Allegation& Mixture)

SBI Clerk 2016- Practice Aptitude Questions (Allegation& Mixture) Set-18:

Dear Readers, Important Practice Aptitude Questions with solution for Upcoming SBI Clerk Exam, candidates those who are preparing for those exams can use this practice questions.

1).In a 25 litres mixture of spirit and water, there is only 50% spirit. 5 litres of this mixture is taken out and 5 litres of pure water is added to the remaining mixture. Find the percentage of water in the final mixture

2).A painter mixes blue paint with white paint so that the mixture contains 10% blue paint. In a mixture of 40 litres paint how many litres of blue paint should be added so that the mixture contains 20% of blue paint ?

3).A container contains 10 litres mixture in which there is 10% sulphuric acid. How much sulphuric acid is to be added to make the solution contain 25% sulphuric acid ?

4).What quantity of water should be added to 3 litres of 10% solution of salt, so that it becomes a 5% salt solution ?

5).The wheat sold by a grocer contained 10% low quality wheat. What quantity of good quality wheat should be added to 150 kg of wheat so that the percentage of low quality wheat becomes 5%?

6).Zinc and copper are in the ratio of 5 : 3 in 200 gm of an alloy. How much grams of copper be added to make the ratio as 3 : 5 ?

7).1 litre of water, is added to 5 litres of alcohol water solution containing 40% alcohol strength. The strength of alcohol in the new solution will be

8).The milk and water in a mixture are in the ratio 7 : 5. When 15 litres of water is added to it, the ratio of milk and water in the new mixture becomes 7 : 8. The total quantity of water in the new mixture is

9).In a 45 litres mixture of milk and water, the ratio of the milk to water is 2 : 1. When some quantity of water is added to the mixture, this ratio becomes 1 : 2. The quantity of water added is

10).A mixture of 30 litres contains milk and water in the ratio of 7 : 3. How much water should be added to it so that the ratio of milk and water becomes 3 : 7?

1).Concentration of water is 50% in mixture and 100% in water

 

[We have 20 litres of mixture and 5 litres of water]

(100 – x) / (x – 50) = 4 / 1

(100 – x) = (4x – 200)

300 = 5x

x = 60%

2).

Ratio = 80 : 10 or 8 : 1

In 40 litres of mixture, 5 litres of blue paint must be mixed, Ratio becomes 40 : 5 or 8 : 1

3).

Ratio = 75 : 15 = 5 : 1

In 10 litres of mixture, 2 litres of sulphuric acid must be added

4).

Ratio = 5 : 5 = 1 : 1

Hence, in 3 litres of solution, 3 litres of water must be added.

5).% of low quality wheat in first mixture = 10%

% of low quality wheat in good quality wheat (to be added) = 0%

Ratio = 5 : 5 = 1 : 1

Hence, in 150 kg of given mixture, 150kg of good quality wheat must be added.

6).Fraction of copper in given mixture = 3 / 8

Fraction of cooper in copper = 1

Ratio = (3 / 8) : (2 / 8) = 3 : 2

In 200 gm of alloy, copper that should be added is calculated as, (3/5)x = 200

x = 200 × (5 / 3) and copper

= 200 × (5 / 3) × (2 / 5)

= 400 / 3 = 133(1 / 3) gm

7).In water, there is 0% alcohol and in mixture there is 40% alcohol

[(40 – x) / (x – 0)] = 1 / 5

200 -5x = x

x = 200 / 6 = 33(2 / 6)% = 33(1 / 3)%

8).Concentration of water in initial mixture = 1/5

Concentration of water in water = 1

Concentration of water in final mixture = 8/15

Ratio = (7 / 15) : (7 / 60) = 4 : 1

Thus, 15 litres of water is added in 60 litres of initial mixture. Quantity of water in final mixture = 60(5 / 12) + 15 = 40 litres

9).Consider concentration of water only

Ratio = (1 / 3) : (1 / 3) = 1 : 1

Hence, in 45 litres of mixture 45 litres of water is added.

10).Consider concentration of water only

Ratio = (3 / 10) : (4 / 10) = 3 : 4

In 30 litres of mixture, 40 litres of water must be added.