SUBTRACTION: Problem 5

Rule 19:

To subtract, the denominators must be equal. You essentially following the same steps as in addition.

1.: Build each fraction so that both denominators are equal.
2.: Combine the numerators according to the operation of subtraction or additions.
3.: The denominators will be the denominator of the built-up fractions.
4.: Reduce the answer.

Problem 5:

Calculate

and reduce your answer.

Answer:

The answer is

Solution:

Convert the whole number 5 to a fraction and rewrite the problem.

tex2html_wrap_inline78 .

The denominators are different; therefore, the first step is to build the fractions to fractions with common denominators.

20 can be factored as follows: 20 = 4 5 and 24 can be factored as follows: 24 = 4 6.

Rewrite the fractions where the denominators are in factored form.

tex2html_wrap_inline84 .

It appears that the common denominators must have the factors 4, 5 and 6. Multiply each fraction by the form of 1 that will yield denominators with the same set of factors. (i.e., you can find each set of factors in the denominator of the answer)

tex2html_wrap_inline86 ,

tex2html_wrap_inline88 , and

tex2html_wrap_inline90 .

Combine the numerators: 600 - 18 - 5 = 577.

The answer is tex2html_wrap_inline96 .

This answer is already reduced so you can skip step 4.

Check:

You can check the answer with your calculator.

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Author:Nancy Marcus