A plumber had a pipe that was 2 yards long he cut 18 inches off the end of the pipe

To convert yards to feet, you would multiply it by 3. So, since there the pipe is 2 yards long, you could multiply 2*3 to get 6 feet. Then you can convert feet to inches by multiplying it by 12. 6*12 is equal to 72, so 2 yards is equal to 72 inches. Lastly, you can subtract 18 from 72, to get 54, and 54 inches would be your final answer.