A propeller revolves 468 times in 52 s. How long will it take the propeller to revolve 756 times?

The propeller revolves 9 times per second. so in 84 seconds it will have revolved 756 times.

It would take 84 seconds for the propeller to revolve 756 times.

756 / 468 = 1.6154

1.6154 * 52 seconds = 84 seconds or 1 minute 24 seconds

If the problem asks for the number of revolution in one minute. then.

1 minute = 60 seconds

52 s / 60 s = 0.8666

468 times : 0.8666 = 540 revolutions.