Question

A girl is 3 years older than her brother in four more years 3 times her age will be 4 times her brother s age find the present age

Answer 1

Answer:

boy = 5 years

girl = 8 years

Step-by-step explanation:

let age of boy = x

let age of girl = y

1) 3+x=y

2)After 4 years:

3(y+4)=4(x+4)

3y +12 = 4x+16

from 1)

3(3+x) + 12 = 4x + 16

9+3x + 12 =4x+16

21+3x=4x+16

21-16 = 4x-3x

5=x

3 + x=y

3+5=y

8 = y

Therefore age of boy is 5 years and age of girl is 8 years

Answer 2

Answer:

boy = 5 years

girl = 8 years

Step-by-step explanation:

let age of boy = x

let age of girl = y

1) 3+x=y

2)After 4 years:

3(y+4)=4(x+4)

3y +12 = 4x+16

from 1)

3(3+x) + 12 = 4x + 16

9+3x + 12 =4x+16

21+3x=4x+16

21-16 = 4x-3x

5=x

3 + x=y

3+5=y

8 = y

Therefore age of boy is 5 years and age of girl is 8 years