Problema Solution
One grocery clerk can stock a shelf in 35 minutes. A second clerk requires 45 minutes to stock the same shelf. How long would it take to stock the shelf if the two clerks worked together?
Answer provided by our tutors
let 'x' be the time in minutes the two clerks need to stock the shelf together
1/35 + 1/45 = 1/x multiply both sides by x*5*7*9 (since Least Common Multiple of 35 and 45 is 5*7*9)
9x + 7x = 315
16x = 315
x = 315/16
x = 19.6875 min
if the two clerks worked together they will need 19.6875 min to stock the shelf.