Alligation & Mixtures Model Questions Set 1 Practice Questions Answers Test with Solutions & More Shortcuts

Answer: (d)

Here, allegation is applicable for 'money per boy or girl".

Mean value of money per student = ${3900}/{65}$ = 60P

∴ Boys : Girls = 3 : 2

∴ Number of boys = ${65}/{3 + 2}$ × 3 = 39

and number of girls = 65 – 39 = 26

Answer: (d)

By the rule of alligation:

∴ Required rate = 3.50 : 1.50 = 35 : 15 = 7 : 3

Answer: (d)

By the alligation rule, we find that wine containing 30% of spirit and wine containing 12% of spirit should be mixed in a ratio 1 : 2 to produce a mixture containing 18% of spirit.

Ratio = 6 : 12 = 1 : 2

This means that $1/3$ rd of the butt of sherry was left, i.e. to

say, the butler drew out $2/3$ rd of the butt.

∴ $2/3$ rd of the butt was stolen.

Answer: (b)

In original mixture, % of liquid B = $1/{4 + 1}$ × 100 = 20%

In the resultant mixture, % of liquid B = $3/{2 + 3}$ × 100 = 60 %

Replacement is made by the liquid B, so the % of B in second mixture = 100%

Then, by the method of Alligation :

∴ Ratio in which first and second mixtures should be added is 1 : 1. What does it imply? It simply implies that the reduced quantity of the first mixture and the quantity of mixture B which is to be added are the same.

∴ Total mixture = 10 + 10 = 20 litres

and liquid A = ${20}/5$ × 4 = 16 litres

Answer: (e)

Initially water (weight) = 45 gm & milk 15 gm. After added 15 gm

water the percentage of water = ${\text"weight of water"}/{\text"total weight of mixture"}$

= ${60}/{75}$ × 100 = 80%