Question

Ruchi is 4 years older than Monica, and the sum of their ages is 20 years. Find their ages​

Answer 1

Answer:

Let the age of Monica be x

Therefore, age of ruchi = x+4

sum of ages = 20

x+x+4 = 20

2x +4 = 20

2x= 20-4

2x = 16

x= 8

Monica =8

Ruchi= 8+4= 12

Answer 2

Answer:

Let, the age of Ruchi = x years

And, the age of Monica = y years

According to the question,

x = 4 + y - (1)

x + y = 20

Putting the value of x from equation (1),

4 + y + y = 20

4 + 2y = 20

2y = 20 - 4 = 16

y = 16/2 = 8

So, putting the value of y in equation (1),

x = 4 + 8 = 12

So, the age of Ruchi and Monica are 12 and 8 years old respectively.