Question

15 years ago the age of man was 20 years more than thrice his son's age . how many years ago was the age of the man thrice his son's age ?​

Answer 1

Answer:

20 years ago the mans age was thrice of his sons age

Answer 2

Answer:

Five years ago the age of man is thrice the age of his son

Step-by-step explanation:

Given,

15 years ago the age of man was 20 years more than thrice his son's age

To find,

How many years ago was the age of the man thrice his son's age

Solution:

Let 'x' be the age of man and 'y' be the age of the son

15 years ago,

The age of man = x - 15 and age of son = y -15

Since 15 years ago the age of man was 20 years more than thrice his son's age, we have

x - 15 = 20 + 3(y-15)

x - 15 = 20 + 3y -45

x = 20 +3y - 45 +15

x = 3y -10 ------------------(1)

Let 'p' years ago the age of man is thrice the age of his son, then we have

x -p = 3(y-p)

Substitute the value of 'x' from equation (1) we get

3y -10 -p = 3(y-p)

3y - 10 -p = 3y -3p

-10 = -3p+p

2p = 10

p = 5

Hence we have,

Five years ago the age of man is thrice the age of his son

#SPJ2