Question 300679
Judy is 12 years older than Joan. In 7 years, the sum of thier ages will be 42. How old is each now?

let joan's age be x

judy's age will be x+12

after 7 years their ages will be x+7  & (x+12) years

x+7 + ( x+12 )+7 = 42

x+7 + x+12 +7= 42

2x+26=42

2x=42-26

2x=12

x=6 which is joan"s age

Judy's age = 12+6 =18 years