Question

Donna is running a track it takes her 10 minutes to run 6 laps if she keeps running at the same speed how long will it take her to run 5 laps

Answer 1

To solve this problem we can make a proportion.
6      5
-- = ---
10    x

to solve this proportion we can cross multiply and divide.
5 times 10 is 50.  divided by 6 is 8.3
it will take her 8.3 minutes to run 5 laps

Answer 2

If Donna took 10 minutes to run 6 laps, it took her 600 seconds to run 6 laps
so that means each lap took 100 seconds to complete. 100*5=500 seconds
so it took her 8 minutes 20 seconds