How do I find the LCD of 1/4.5 and 1/3?

Question

I have to solve a problem that is like this, 1/4.5 + 1/3 = 4/5 But I don't know how to find the LCD of a decimal and an integer.

Answer 1

Hi Eve, there are several ways to work this type of problem. To find the LCD for 4.5, 3, and 5, we can set up a table to find where all three numbers divide into the same number.

 

Example:

 

  4.5        3         5

---------------------

  4.5        3         5

  9           6        10

  13.5      9         15

 

and keep going until we get to a number that all three can divide into. In this case the number is 45. 4.5 divides into 45 exactly 10 times.

 

3 divides into 45 exactly 15 times and 5 divides into 45 exactly 9 times.

 

The LCD is 45.

 

Another way to work this problem without finding the LCD, is to multiply the entire equation by (4.5 * 3 * 5). This will clear all of the fractions.

 

Questions?