Question

if a worker can pack 1/6 of a carton of canned food in 15 minutes and there are 40 workers in a factory, how many cartons should be packed in the factory in 1#1/2 hours?

Answer 1

in 15 minutes one worker can pack =1/6 carton
in 15 minutes 40  workers can pack = 1/6*40 = 40/6 = 20/3
1 1/2 hours =90 minutes 
20/3 *1/3 *90 = 40 cartons ( in simplest form )