10 years ago a was half of b in age . if the ratio of their present ages is 3 : 4 , what will be the total of their present ages
explanation : let a ' s age 10 years ago = x years . then , b ' s age 10 years ago = 2 x years . ( x + 10 ) / ( 2 x + lo ) = 3 / 4 = > x = 5 . so , the total of their present ages = ( x + 10 + 2 x + 10 ) = ( 3 x + 20 ) = 35 years . answer : option b
add(multiply(3, divide(subtract(10, divide(10, const_2)), subtract(3, divide(4, const_2)))), multiply(4, divide(subtract(10, divide(10, const_2)), subtract(3, divide(4, const_2)))))