Quiz-1

Let Virat Kohli present age be x
Virat Kohli age before 5 years = x - 5
Virat Kohli age after 10 years = (x + 10)
We are given that, Virat Kohli age after 20 years (x + 10) is 5 times his age 5 years back (x – 5)
Therefore, (x + 10) = 5 (x – 5)
Solving the equation, we get x + 10 = 5x – 25
x = 8.75 years

Let age of Ms.dhoni be y
Yuvraj is 15 years elder than Ms.Dhoni = (y + 15). So Yuvraj age 5 years ago = (y + 15 – 5).
Ms.dhoni age before 5 years = (y – 5)
5 years ago, Yuvraj was 3 times as old as Ms.Dhoni
(y + 15 – 5) = 3 (y – 5)
(y + 10) = (3y – 15)
2y = 25 ⇒ y = 12.5
Ms.dhoni’s age = 12.5 years
Yuvraj's age = (y + 15) = (12.5 + 15) = 27.5 years.

Here, we have to calculate: How many years ago the ratio of their ages was 4:3.
Let us assume x years ago
At present: Anjali is 45 years and Harsh is 35 years
x years ago: Anjali’s age = (45 – x) and Hrash's age = (35 – x)
Given, the ratio of their ages was:4:3
\frac{ (45-x) }{(35-x) } = \frac{4}{3}
Solving, we get: x = 5

Therefore, the answer is 5 years.

Let the present age of the daughter be P, She was born P years ago.
The age of the Mother was: (50 - P).
His age when the son was born should be equal to \frac{1}{4} of P.
(50 - P) =\frac{1}{4}P
⇒ P = 40

Let Raman’'s age be x years.
Then, Daksh 's age = (x - 9) years.
\frac{(x - 9)}{x} = \frac{4}{5}
x = 45
Hence, Daksh's age = (x - 9) = 36 years

Let us assume Max’s current age as m.

Then, Nick's current age will be =3m.

m + 12 =\frac{3m + 12}{2}
3m+12
2(m + 12) = (3m + 12)
2( m + 12) = 3m + 12
2m + 24 = 3m + 12
m = 12
nicks present age = 3m = 36
Nicks age 6 years hence= 36 + 6 = 42

If the youngest child’s age is assumed as a.

Then, ages of all the four children can be defined as a , (a+2), (a+4), (a+6)

Given, a + (a+2) + (a+4) + (a+6) = 40
4a = 40 – 6 – 4 – 2
4a = 28
a = 7
Hence the youngest kid is 7 and the eldest one is 7 + 6 = 13 years.

Let the present age of son = x yrs
Then, the present age of the father = 5x yrs
3 years ago,
7(x - 3) = 5x - 3
Or, 7x - 21 = 5x - 3
Or, 2x = 18 ∴ x = 9 yrs
Therefore, son’s age = 9 yrs
Father’s age = 45 yrs

10 years ago, A was \frac{1}{2} of B’s Age.
At present, A is \frac{2}{4} of B’s Age.
∴ B’s age [use formula (1)] = \frac{10\left( \frac{1}{2} - 1 \right)}{\frac{1}{2} - \frac{3}{4}} = 20 yrs
A’s age = \frac{3}{4} of 20 = 15 yrs

Let the age of the son be x yrs.
Then, the age of the father is (56 - x) yrs.
After 4 yrs, 3(x + 4) = 56 - x + 4
Or, 4x = 56 + 4 - 12 = 48
Therefore, x = 12 yrs.
Thus the age of the son is 12 yrs.