Question

How do you evaluate `4\times 2\frac{1}{2}+5\frac{3}{4}`?

Answer 1

63/4 or 15.75

Explanation:

You can choose to do this in fractional or decimal form. I'll go through both.

Decimal
`2 1/2 = 2.5 and 5 3/4 = 5.75`

So equation becomes `4 times 2.5 + 5.75 = 10 +5.75=15.75`

Fractions
First rearrange everything so it's all improper fractions.

`4/1 times 5/2 + 23/4`

Rule for multiplying fractions: top times top, bottom times bottom.

`4/1 times 5/2 = 20/2 = 10`

Now we have `10/1 + 23/4`

Rule for adding fractions: add the top line IF the denominators (bottom line) are equal.

It's easier to make `10/1` have a denominator of 4, because 23 is a prime number so we can't divide it by anything except itself.

`10/1 + 23/4 = 40/4+23/4`

Now add the top lines:

`40/4 +23/4 = 63/4`