Question

jumbo can repair a machine in 1 hour 30 minutes. he asks Rambo to give him support in the process of repair together, they star doing the repair and complete the task in 1 hour only. had Rambo been given this task, how much time would he have taken to repair the machine?

Answer 1

Answer:

180 minutes or 3 hours.

Step-by-step explanation:

If Jumbo repairs the machine 100% in 1 hr 30 min(90 min).

In 1 min he'll repair (100/90)% of the machine.

Let's assume, Rambo takes X min to repair the same machine at its 100%.

Thus, in 1 min he repairs (100/X)% of the machine.

Together they need 60 min to repair the same machine.

Thus, in 1 min together they complete (100/60)% of the machine.

According to the question,

100/90) + (100/X) = 100/60

or, 1/90 + 1/X = 1/60

or, 1/X = (1/60 - 1/90)

or, 1/X = 1/180

or, X = 180

Thus, Rambo needs 180 minutes to repair the machine completely.