A motorboat traveling with the current went 9mi in 1 h against the current it took 3h to travel the same distance find the rate of the boat in calm water and the rate of the current

Find the average between the two rates. That's how you can get the rate of the boat, which is 6 mph. To find the rate of the current, find the difference between the rate of the boat with either of the two given rates. This should give the rate of the current as 3 mph.