How To: Solve a word problem that involves proportions

In this Education video tutorial you will learn how to solve a word problem that involves proportions. To solve such problems you got to express the scenario in proportions. For example, in the problem, 'Jacob ran 10 miles in 80 minutes'; this rate can be expressed as 10miles/ 80 minutes. The second part of the problem is to find out 'at that rate how far would he run in 2.5 hours'? 'How far' being a variable, write it as 'x' and this can be expressed as x/ 2.5 hours. So, the complete equation now becomes 10miles/ 80 minutes = x/ 2.5 hours. Now converting 2.5 hours to minutes, you get 150minutes. So, the equation now becomes 10miles/ 80 minutes = x/ 150 minutes. Now doing cross multiplication we get 1500 = 80x, or x = 1500/80 = 18.75. Hence, the answer is at that rate Jacob will run 18.75 miles in 2.5 hours. This is how you solve word problems with proportions.