Math Question about Rational Numbers

Question

Between

9

P.M. and

6:54

A.M.​,

the water level in a swimming pool decreased by

11/20 in.

Assuming that the water level decreased at a constant​ rate, how much did the water level drop each​ hour?

Answer 1

dropped 11/20 inch in 594 minutes how much in 60 minutes=1 hour?

from 9pm to 6:54 am is 9 hours 54 minutes = 9(60)+54= 594 minutes

x/60 = (11/20)/594,

solve for x, cross multiply

594x = 33

x= 33/594 = 11/198 = 1/18 inch in one hour