Proportions relationships and percentages

Question

A circular running track 1/4 mile long, Beth runs on this track completion each lap in 1/10 of an hour.

What is Beth running speed?

Answer 1

Hi Michelle! The first thing you need to do to approach this problem is to know how speed is written. Since this problem is using miles, we will be using the american mileage system. Speed is written as miles per hour. Because this fraction always has 1 hour as the denominator, we need to adjust this in the problem.

1/4 mile x miles

_______ x _______

1/10 hour 1 hour

What is the factor used to multiply 1/10 to get 1 hour? This would be 10. Since this is a fraction, we need to do whatever we did to the denominator to the numerator as well, so we are not technically changing the fraction. So, we multiply 1/4 by 10. This is 10/4, reduced as 2 and 1/2. This means that the speed at which Beth is running is 2 1/2 miles per hour. Hopefully this helps!