Average speed is total distance over total time. Do not average the two speeds. 60 miles at 30 mph and 60 miles at 60 mph is 120 miles in 3 hours, so 40 mph, not 45. Rate problems as a set are in rate, distance, and work.
Add the pieces first
Find each leg's time if you were given distance and speed. Add the distances. Add the times. Then divide. Mean of a list of numbers is a different formula, in mean, median, and mode.
Unit conversions on hours and minutes are in unit conversions. Word-problem setup is in setting up word problems.
The bottom line
Total distance divided by total time. Never average the speeds unless the times were equal and the question asked for that.
Start practicing
Start with a free diagnostic, then drill your weak spots with 15-question quizzes and track how you're doing across Reading, English, and Math. Compare plans whenever you're ready to go further.
This article offers general ACT prep guidance. The ACT can change from year to year, including its format, scoring, policies, test dates, and fees, so always confirm the latest details on the official ACT website at act.org before you make decisions. ACT® is a registered trademark of ACT, Inc. thirty-six is not affiliated with, endorsed by, or sponsored by ACT.