LoyalWater wrote:

Working alone at its own constant rate, a machine seal k cartons in 8 hours, and working alone at its own constant rate, a second machine seals k cartons in 4 hours. If the two machines, each working at its own constant rate and for the same period of time, together sealed a certain number of cartons, what percent of the cartons were sealed by the machine working at the faster rate?

a) 25%

b) 33 1/3 %

c)50%

d)66 2/3 %

e) 75%

This question has been discussed on the forums earlier but there is not solution that explains how to get the Ans.

Can someone please help me with this one.

In 8 hours, machine 1 will seal k cartons.

In 8 hours, machine 2 will seal 2k cartons.

Total cartons in 8 hours = 3k

Total cartons sealed by fast machine = 2k/3k = 66 2/3%