In 5 years, Andy will be twice as old as Rahim is now. Rahim is 6 now. How much older is Andy than Rahim, right now, in years?
Andy will be 2*6=<T>multiply(2, 6)=12
Now he is 12-5=<T>subtract(12, 5)=7
So Andy is 7-6=<T>subtract(7, 6)=1 year older than Rahim.
