## The Basics of Inverse Proportion

In the previous post, we have discussed the basics of direct proportions. Recall that when two quantities $x$ and $y$ change and if $x$ changes n times, then $y$ changes n times, then we can say that $y$ is directly proportional to $x$. In this post, we are going to learn about inverse proportions.

Problem

A rectangle has area 24 square units. Find the possible areas if the length and width are both whole numbers.

Solution and Discussion

The table shows the pairs of length and width that has area of 24 square units.  » Read more

## The Basics of Direct Proportion

A car travels at 40 kilometers per hour traveled for 7 hours. The table of the distances traveled with respect to time is shown below.

Observe the relationship between the distance traveled and the time. As the time increases, the distance traveled increases. If the number of hours increases two times, then the distance also increases two times. Between hour 1 and hour 2, the increase in time is 1 hour, and the increase in distance is 40 kilometers. Between hour 3 and hour 5, the increase in time is 2 hours, and the increase in distance is 2(40) = 80 kilometers. If there are two changing quantities $x$ and $y$ and if the value of $x$ changes 2 times, 3 times, and so on, $y$ also changes 2 times, 3 times, and so on respectively, we can say that $y$ is directly proportional to $x$. In the relationship above, distance is directly proportional to time.  » Read more