a boy is 17 tears old and his sister is twice as old. when the boy turns 23 yrs old what will be the age of his sister?
So,
We know that the boy is half as old as his sister.
Boy now = 17
Sister now = 34
Boy + 6 = 23
So, we add 6 to the sister's current age.
34 + 6 = 40
The sister will be 40 years old.
b=17
s=2b=17(2)=34
so
34-17=17 therefor
s-17=b
so
s-17=23
add 17 to both sdies
s=40
sister will be 40