Ratio & Proportion (2)

1. A is two years older than B who is twice as old as C. The total of the ages of A, B and C is 27. How old is B?
1. 10
2. 9
3. 8
4. 7

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Answer:- 1

Explanation :-

Let the age of C = x years
Therefore, B’s age = 2x years  &  A’s age = (2x + 2) years
x + 2x + (2x + 2) = 27
5x + 2 = 27
x = 5
So , B’s age =  2x = 2 * 5 = 10 years

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2. A man’s age is 125% of what it was 10 years ago, but 8313% of what it will be after 10 years. What is his present age?
1. 70
2. 60
3. 50
4. 40

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Answer:- 3

Explanation :-

Lets assume the age before 10 years = x , Therefore
(125x/100) = x + 10
125x = 100x + 1000
25x = 1000
x = 40
His present age = x + 10 = 40 + 10 = 50 years

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3. A man is 24 years older than his son. In two years, his age will be twice the age of his son. What is the present age of his son?
1. 23 years
2. 22 years
3. 21 years
4. 20 years

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Answer:- 2

Explanation :-

Let’s suppose son’s present age = x years.
Therefore, man’s present age = (x + 24) years
(x + 24) + 2 = 2(x + 2)
x + 26 = 2x + 4
x = 22

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4. Present ages of Kiran and Syam are in the ratio of 5 : 4 respectively. Three years hence, the ratio of their ages will become 11 : 9 respectively. What is Syam’s present age in years?
1. 28
2. 27
3. 26
4. 24

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Answer:- 4

Explanation :-

Kiran’s age : Syam’s age = 5x : 4x
Let’s suppose  the present age of Kiran  = 5 x
Present age of Syam = 4x
After 3 Years, Ratio Become 11 : 9
That means (5x + 3) / (4x + 3) = 11/9
9(5x + 3) = 11(4x + 3)
45x + 27 = 44x + 33
x = 6 years
Syam’s Present age = 4x = 4 * 6 = 24 years

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5. The sum of ages of 5 children born at the intervals of 3 years each is 50 years. Find out the age of the youngest child?
1. 6 years
2. 5 years
3. 4 years
4. 3 years

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Answer:- 3

Explanation :-

Let the age of younger child = x years
As there is a gap of 3 years in ages of all the 5 childrens
Therefore According to question
x + (x + 3) + (x + 3) + (x + 3) + (x + 3) = 50
5x = 20
x = 4
Age of  younger child = 4 years

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