a man can do a piece of work in 6 days , but with the help of his son , he can do it in 3 days . in what time can the son do it alone ?
"son ' s 1 day ' s work = ( 1 / 3 ) - ( 1 / 6 ) = 1 / 6 the son alone can do the work in 6 days answer is c"
divide(multiply(6, 3), subtract(6, 3))