if a is thrice as fast as b and together can do a work in 18 days . in how many days a alone can do the work ?
"a ’ s one day ’ s work = 1 / x b ’ s one day ’ s work = 1 / 3 x a + b ’ s one day ’ s work = 1 / x + 1 / 3 x = 1 / 18 = 3 + 1 / 3 x = 4 / 3 x = 1 / 18 x = 18 * 4 / 3 = 24 answer : c"
inverse(divide(const_3, multiply(18, const_4)))