Solve these sums to grasp ratio and proportion concept well

Here are some practice questions along with solutions that will help you in your preparation for the State government recruitment tests.

Hyderabad: This article is in continuation to the last article focusing on the ratio and proportion topic. Here are some practice questions along with solutions that will help you in your preparation for the State government recruitment tests.

1. The number of students in school A, B and C are in a ratio of 5 : 4 : 8 respectively. If the number of students is increased by 40%, 75% and 25% respectively in next year and the total students after increment is 1,200, what was the total number of students initially?
a) 750 b) 800 c) 850 d) 900
Answer: c

Solution: Let the students in school A, B and C = 5x, 4x, 8x

After the increment, students in school A = 5x × 140% = 7x
After the increment, students in school B = 4x × 175% = 7x

After the increment, students in school C = 8x × 125% = 10x
According to the question,

7x 7x 10x = 1200

24x = 1200

x = 50

Students in School A initially = 5 × 50 = 250

Students in School B initially = 4 × 50 = 200

Students in School C initially = 8 × 50 = 400

Required number of students = 250 200 400 = 850

2. In a town with population of 4,500, the ratio of males to females is 3 : 2 and the ratio of females to children is 4 : x. In election of Nagar – Palika, two candidates are there, children aren’t allowed to vote and 10% of the eligible population didn’t cast their vote. If the winner candidate won by 400 votes and the runner-up candidate got 1,150 votes, then find the value of ‘x’.

[Note: Total population of village = Male Female Children]
a) 3 b) 5 c) 2 d) 8
Ans: b
Solution:
Total votes got by winner and runner-up = (1150 400) 1150 = 2700

These 2,700 votes are given by 90% of male and female as 10% of male and female did not cast their vote.
So, 90% of total male and female = 2700
So, total male female = 3000
Therefore, number of children = 1500
Ratio of Male : Female : children =3×2 : 2×2 : x = 6 : 4 : x
The number of children is 1,500 which is half of the total number of male and female which is 3,000.

So, x will be half the number of parts of male and female in the ratio which will be equal to 5 as total part of male and female is (6 4 = 10).
To be continued…

M Venkat
Director

MVK Publications

Dilsukhnagar

7671002120