Derrick lives 3 miles from the park. he rode his bicycle to the park at an average speed of 9 miles per hour. how many minutes did it take derrick to ride his bicycle to the park?

Hey there!

Since we don't know how many hours it took, we'll say 9 mph = 3 miles/x hours. To solve, we multiply both sides by x. 9x = 3 Dividing both sides by 9, we get that it took 3/9 hours or 1/3 hours. How many minutes are 1/3 hours? 20, so it took Derrick 20 minutes. Hope this helps! :)

Hugs! 
- Nicole

You'll have to compass tip on A and draw a small ark with pencil approximately in the middle above AB line, now compass tip to point B and cross the ark you made previously.
Do the same on the opposite side without making any change to the compass 
Join the lines where crosses of arks on the both side meet and then ,it's done.