david is 12 years older than his daughter rosy . in 4 years david will be twice as old as rosy . what is rosy current age .
"now : rosy = x , david = x + 12 in 4 years rosy = x + 4 , david = x + 12 + 4 or 2 ( x + 4 ) x + 16 = 2 x + 8 x = 8 rosy is 8 years old answer : d"
subtract(add(12, 4), multiply(const_2, 4))