chelsea ran a marathon. It took 5.5 hours to run 26.2 miles. Find her average speed in miles per hour. Then convert her speed to feet per second

Question

i mile =5,280 feet

Answer 1

26.2 mi / 5.5 hr = 4.7636363...... ^mi/_hr

 

Now to convert:

^{4.7636363... mi} / _hr * ^{5280 ft} / _mi * ^{1 hr} / _{3600 sec}

Cancel out the units:

4.7636363... * ^{5280 ft} / _{3600 sec}

 

We can factor out 40:

4.7636363... * ^{132 ft} / _{90 sec}

We can even factor out another 6:

4.7636363... * ^{22 ft} / _{15 sec} = 9.98666... ^ft/_sec