To get the answer you need to find out how many miles she bikes in 10minutes.
Divide 50minutes by 10 you get 5. Now you divide 10(miles) by 5 and you get 2. So it means that in 10minutes she bikes 2miles. Now you need to know how many miles she bikes in 90minutes so if she bikes 2 in 10 then because 90:10=9 you do 2*9=18. She can bike 18miles in 90minutes. :))
The dragons would have to speed up to balance out the time that they slowed down.
The instantaneous rates of changes are all the individual speeds at given times. If you have some that are slow, you will need to have just as many that are fast to balance it out and ensure they have the correct average speed.
Area of square is a^2
4^2 = 16
the area is 16 units
