How do you simplify $\frac{15}{2} - 45$ $\frac{15}{2}-45$ ?

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Answer 1 · 2017-06-14T04:14:15

The solution is $- \frac{75}{2}$ $-75/2$ .

To subtract numbers involving fractions, both have to have the same DENOMINATOR.

$\frac{15}{2}$ $15/2$ has the denominator 2.
$- 45$ $-45$ has the denominator 1.

Since 2 and 1 are not the same, change $- 45$ $-45$ to have a denominator of 2 to make both fractions have the same denominator.

To give $- 45$ $-45$ a denominator of 2, multiply $- 45$ $-45$ by $\frac{2}{2}$ $2/2$ .

[We can multiply by $\frac{2}{2}$ $2/2$ because $\frac{2}{2} = 1$ $2/2 = 1$ , which means we didn't change the original problem! ]

You should end up with $\frac{15}{2} - \frac{90}{2}$ $15/2 - 90/2$ .
[The 90 came from $- 45 \cdot 2 = - 90$ $-45 * 2 = -90$ ]

Now that they have the same denominator, subtract 90 from 15 to get your new numerator, $- 75$ $-75$ !
$15 - 90 = - 75$ $15-90=-75$

Keep the DENOMINATOR as $2$ $2$ because when subtracting fractions, the denominator DOES NOT CHANGE.

$- \frac{75}{2}$ $-75/2$ cannot be simplified, so your final answer should be $- \frac{75}{2}$ $-75/2$ .

How do you simplify 152−45\frac{15}{2}-45?