Question

« UNILO
. Tulu the fraction.
2
Find their present ages.
21. A man is twice as old as his son. 20 years ago, the age of the man was 12 times the age of these​

Answer 1

Correct Question:

A man is twice as old as his son. 20 years ago, the age of the man was 12 times the age of these. Find their present ages.

Step-by-step explanation:

Assume that the present age of son is x years.

A man is twice as old his son. Therefore, the present age of man is 2x years.

20 years ago:

• Age of son = (x - 20) years
• Age of man = (2x - 20) years

As per given condition,

→ (2x - 20) = 12(x - 20)

→ 2x - 20 = 12x - 240

→ 12x - 2x = 240 - 20

→ 10x = 220

→ x = 22

So,

Present age of boy = x = 22 years

Present age of man = 2x = 2(22) = 44 years

Therefore, the present age of son is 22 years and man is 44 years.

Answer 2

Solution :

Let the age of the son be r years & the man age be 2r respectively;

A/q

$\underbrace{\bf{20\:years\:ago\::}}$

The age of son's was = (r-20) years.

The age of man's was = (2r-20) years.

Now;

$\longrightarrow\sf{(2r-20) = 12(r - 20)}\\\\\longrightarrow\sf{2r-20 = 12r - 240}\\\\\longrightarrow\sf{2r-12r = -240 + 20}\\\\\longrightarrow\sf{-10r = -220}\\\\\longrightarrow\sf{r=\cancel{-220/-10}}\\\\\longrightarrow\bf{r=22\:years}$

Thus;

The present age of son's will be r = 22 years .

The present age of man's will be 2r = 2×22 = 44 years .