Question

A map is made to a scale of 1/4 inch is to 12 inches. What is the actual length of a room in feet whose length on the map is 3 3/8 inches?

Answer 1

In this example, we are to find the actual length of a room based from its length on the map by using ratio and proportion.
For our solution to be more clearer, let us turn the fractions into decimals.
1/4 inch = 0.25 in.
3 3/8 inches = 3.375 in.

So, for every 0.25 inches from the map there will be 12 inches in the room, and what we will find here is that how many inches are there in the room if there are 3.375 inches in the map.

Let x, be the length in the room,
$\frac{0.25}{12} = \frac{3.375}{x}$
Cross multiply the given fractions and you would get:
$0.25x=40.5$
$x=162$

So the length of the room, if the value of it in the map is 3 3/8 inch, is 162 inches.