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

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Answer 1 · 2017-09-24T03:37:04

63/4 or 15.75

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:

$40/4 +23/4 = 63/4$

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