SSC CGL 2015 : Quant Quiz(ages)

1.The age of father 3 years ago was 8 times the age of his son. Presently the father’s age is 5 times that of the son. Find their present ages. 

(a) 35 

(b) 30 

(c) 38 

(d) 40

2.The present age of A is 9 times the present age of B. 3 years hence A’s age will be 5 times that of B. Find their present ages. 

(a) 25 

(b) 23 

(c) 19 

(d) 27

3.The ratio of Ram’s present age to Mohan’s present age is 5 : 6.  8 years hence this ratio changes to 7 : 8 Find their present ages. 

(a) 18 

(b) 19 

(c) 20 

(d) 21

4.The sum of present ages of Rohit and Mohit is 30 years. 5 years hence the ratio of their ages will be Rohit : Mohit : : 5 : 3. Find their present ages. 

(a) 18 

(b) 19 

(c) 21 

(d) 20

5.The average age of a man and his son is 35 years. The ratio of their ages is 5 : 2 respectively. What is the son’s age? 

(a) 50 years 

(b) 35 years 

(c) 15 years 

(d) 20 years 

6.The ages of Aarzoo and Arnav are in the ratio of 11 : 13 respectively. After 7 years the ratio of their ages will be 20 : 23. What is the difference in years between their ages? 

(a) 4 years 

(b) 7 years 

(c) 6 years 

(d) 5 years

 7.The ratio between the ages of Ram and Mohan is 4 : 5 and that between Mohan and Anil is 5 : 6. If sum of the ages of three be 90 years. How old is Mohan? 

(a) 24 years 

(b) 20 years 

(c) 30 years 

(d) 25 years

8.The age of father is three times the age of his son at present. Four years hence the ratio between the ages of father and son becomes 13 : 5 respectively. What is the present age of father? 

(a) 48 years 

(b) 42 years 

(c) 52 years 

(d) Cannot be determined 

9.Harsha is 40 years old and Rita is 60 years old. How many years ago  was the ratio of their ages 3 : 5 ? 

(a) 10 years 

(b) 20 years 

(c) 37 years 

(d) 5 years

10. Present ages of Radha and sudha are in the ratio of 7 : 9 respectively. Five years ago ratio of their ages was 3 : 4. What will be Sudha’s age after 3 years from now? 

(a) 48 years 

(b) 42 years 

(c) 43 years 

(d) 38 years

Answers and Solution:

1.(a) Let the present age of son be x years.
Then, the present age of father = 5x years.
3 years ago,
Son’s age = (x -3) years
Father’s age = (5x – 3) years
But 3 years ago the father’s age was 8 times that of his son.
Therefore, we can write.
8 (x -3) = 5x -3
or, 8x  - 24 = 5x -3
or, 3x = 21
or, x = 7 years
and 5x = 35
We get the present age of son = 7 years
and the present age of father = 35 years

2.(d) Let the present age of B be x years.
Then, the present age of A = 9x years
3 years hence,
B’s age = (9x + 3) years.
But it is given that 3 years hence A’s age will be 5 times the age of B.
so 9x + 3 = 5(x + 3 )
Or, 9x + 3 = 5x + 15
Or, 4x = 12
Or, x =3
B’s present age = 3 years
A’s present age = 9 * 3 = 27 years
3.(c)
4.(d)
5.(d) Let the present ages of father and son be 5x and 2x years respectively.
According to the question.
=> 5x + 2x = 2 * 35
=> 7x = 70
=> X = 70/7 = 10
so son's age = 2x =  2 x 10 = 20

6.(c)Let the present ages of Aarzoo and Arnav be 11x and 13x years respectively,
According to the question,
=> (11x+7)/(13x+7)=20/23
=> 260x + 140 = 253x + 161
=> 260x – 253x = 161 – 140
=> 7x = 21
=> X = 21/7 = 3
Difference between their ages
= 13x – 11x = 2x = 2 * 3 = 6 years

7.(c) Ram : Mohan = 4 : 5
Mohan : Anil = 5 : 6
Ram  : Mohan : Anil = 4 : 5 : 6
so Mohan’s age = 5/15 * 90 = 30 years
 
8.(a) Present age of son = x years then father’s present ages =3x years
According to the question
(3x+4)/(x+4)=13/5
=> 15x + 20 = 13x + 52 = 2x = 32
so X = 16
so Present age of father = 3 * 16 = 48 years

9.(a)Let x years ago the radio of their ages was 3 : 5
so According to the question
(40-x )/(60-x )=3/5
Or, 200 – 5x = 180 – 3x
or, 2x = 20
so X = 10 years
10.(a)