Infosys Problems On Ages Questions and Answers Quiz -1

Let the daughter  age be x and father  age be 4x.
So as per question, 4x + 5 = 3(x + 5). So x = 10.
Hence present age of daughter is 10 years and present age of father is 40 years.
So after 5 + 5 = 10 years, daughter age would be 20 years and father’s age would be 50 years.
Hence father would be 50/20 = 2.5 times of daughter’s age

1) Let age of Rohan be y
2) Rahul is 15 years elder than Rohan = (y + 15). So Rahul’s age 5 years ago = (y + 15 – 5)
3) Rohan’s age before 5 years = (y – 5)
5 years ago, Rahul is 3 times as old as Rohan
(y + 15 – 5) = 3 (y – 5)
(y + 10) = (3y – 15)
2y = 25
y = 12.5
Rohan’s age = 12.5 years
Rahul’s age = (y + 15) = (12.5 + 15) = 27.5 years

Video solution:

10 years ago, age of mother was three times the age of her son. Say, the age of son was x and mother\'s age was 3x.
At present: Mother age is (3x + 10) and son’s age is (x + 10)
After ten years: Mother age will be (3x + 10) +10 and son’s age will be (x + 10) + 10. Given that, mother’s age is twice that of son after ten years.
(3x + 10) +10 = 2 [(x + 10) + 10]
(3x + 20) = 2[x + 20]
Solving the equation, we get x = 20
(3x + 10): (x + 10) = 70: 30 = 7: 3

We are given that age ratio of Harry : Pitter = 5 : 6
Harry’s age = 5x and Peter’s age = 6x
One year ago, their age was 5x and 6x. Hence at present, Harry’s age = 5x +1 and Peter’s age = 6x +1
After 4 years,
Harry’s age = (5x +1) + 4 = (5x + 5)
Peter’s age = (6x +1) + 4 = (6x + 5)
After 4 years, this ratio becomes 6 : 7.

Therefore, Harry's Age/Peter's Age = 6/7

=>(5x + 5) / (6x + 5) = 6 / 7
=>7 (5x + 5) = 6 (6x + 5)
=>X = 5
Peter’s present age = (6x + 1) = (6 x 5 + 1) = 31 years
Harry’s present age = (5x + 1) = (5 x 5 + 1) = 26 years

Let us assume x years ago
At present: Sharad is 60 years and Santosh is 80 years
x years ago: Sharad’s age = (60 – x) and Santosh’s age = (80 – x)
Ratio of their ages x years ago was 4 : 6

So, (60-x)/(80-x) = 4/6

=>6(60 – x) = 4(80 – x)
=>360 – 6x = 320 – 4x
=>x = 20
Therefore, 20 years ago, the ratio of their ages was 4 : 6

Let, x=Present age of brother

5 years ago sister’s age was 5 times the age of her brother.
Therefore,
(34 – x) – 5 = 5 (x – 5)
=>34 – x – 5 = 5x – 25
=>5x + x = 34 – 5 +25
=>6x = 54
=>x = 9
Future age (after 6 yrs) = (x + 6) = (9 + 6) = 15 years

Let daughter’s age be x and father’s age be 3x.
Father’s age is 3 times more aged than his daughter, therefore father’s present age = x + 3x = 4x
After 5 years, father’s age is 3 times more than his daughter age.
(4x + 5) = 3 (x + 5)
=>(4x+5)=3 (x+5)
=>(4x + 5) = 3 (x + 5)
=>x = 10

After 5 years it was (4x + 5), then after further 5 years, father’s age = (4x +10) and daughter’s age = (x + 10)

So, (4x+10)/(x+10) = [(4 × 10) + 10]/[10+10] = 50/20 = 2.5

After further 5 years, father will be 2.5 times of daughter’s age.

Let the age of the youngest child $=x$

Then, the ages of $5$ children can be written as $x,(x+3),(x+6),(x+9)$ and $(x+12)$

$x+(x+3)+(x+6)+(x+9)$ $+(x+12)=50$
$\Rightarrow 5x+30=50\Rightarrow 5x=20\Rightarrow x=\frac{\mathrm{20/}}{5}=4$

Total age of all students $=22\times 21$

Total age of all students + Age of the teacher $=23\times 22$

Age of the teacher
$=23\times 22-22\times 21=22(23-21)=22\times 2=44$

Let son  present age be $x$ years. Then,

$(38-x)=x\Rightarrow 2x=38\Rightarrow x=\frac{\mathrm{38/}}{2}=19$

Sons age $5$ years back =$19-5=14$