The length of a rectangle is 7 1/2 inches and the width is 4 3/4 inches. what is the ratio, using whole numbers, of the length to the width? a. 30: 38 b. 30: 19 c. 15: 19 d. 19: 30

Ratio is a division in its simplest form. 
To get the ratio of length to width, divide the two then simplify.

In this case, convert the length and width into decimals.

length = 7 1/2 = 7.5
width 4 3/4 = 4.75

ratio of length to width is;
7.5/4.75 = 750/475

This can now be written as; 
750 : 475
Dividing both sides by 25;

= 750/25: 475/25

= 30 : 19
 

To solve this problem you must apply the proccedure shown below:

 1. You have the following information given in the problem above:

 - The length of a rectangle is 7 1/2 inches and its width is 4 3/4 inches

 2. Therefore, the ratio is:

 7 1/2 inches=7.5 inches=15/2=30/4
 4 3/4 inches= 4.75 inches=19/4

 length:width
 30:19

 The answer is the option b: B. 30:19