the ratio between the present age of p and q is 6 : 7 . if q is 4 years old then p , what will be the ratio of the ages of p and q after 4 year ?
"solution let p ' s age and q ' s age be 6 x years and 7 x years respectively . then , 7 x - 6 x = 4 ⇔ x = 4 . ∴ required ratio = ( 6 x + 4 ) : ( 7 x + 4 ) = 28 : 32 = 7 : 8 . answer c"
divide(add(4, add(4, divide(multiply(6, 4), subtract(7, 6)))), add(4, divide(multiply(6, 4), subtract(7, 6))))