A copy machine makes 171 coies in 4 minutes and 45 seconds. How many copies does it make per minute?

36

Step-by-step explanation:

171 / (4+0.75) = 36

you want it to be in minutes, so calculate the 45 seconds over 60 seconds, which is 0.75. Add that to the 4 minutes, and divide the total number of copies over the time used, and you have speed/minute.