model 10 percentage with allegations & mixture Practice Questions Answers Test with Solutions & More Shortcuts

Question : 16 [SSC CGL Prelim 2007]

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

a) 33$1/3$%

b) 30%

c) 33%

d) 33$2/3$%

Question : 17

In what ratio must a mixture of 30% alcohol strength be mixed with that of 50% alcohol strength so as to get a mixture of 45% alcohol strength ?

a) 3 : 1

b) 1 : 2

c) 1 : 3

d) 2 : 1

Question : 18

An ore contains 25% of an alloy that has 90% iron. Other than this, in the remaining 75% of the ore, there is no iron. To obtain 60 kg of pure iron, the quantity of the ore needed (in kgs) is approximately :

a) 300

b) 250.57

c) 266.67

d) 275.23

Question : 19

A litre of pure alcohol is added to 6 litres of 30% alcohol solution. The percentage of water in the solution is

a) 40%

b) 50%

c) 65%

d) 60%

Question : 20

A sample of 50 litres of glycerine is found to be adulterated to the extent of 20%. How much pure glycerine should be added to it so as to bring down the percentage of impurity to 5% ?

a) 149 litres

b) 155 litres

c) 150 litres

d) 150.4 litres