Fraction Addition and Multiplication

Multiplication: Multiplying two fractions together is quite simple. Given that multiplication is commutative (we can do it in any order), we simply perform the fractional operations of multiplication and division in sequence.

$\frac{2}{3} \times \frac{4}{5} = 1 \times 2 \div 3 \times 4 \div 5 = \frac{2 \times 4}{3 \times 5} = \frac{8}{15}$

Division: Since division is simply the inverse of multiplication, we can divide one fraction by another be inverting the division and multiplication operations (that is, we mulitply by the reciprocal):

$\frac{2}{3} \div \frac{4}{5} = \frac{2}{3} \times \frac{5}{4} = \frac{2 \times 5}{3\times 4} = \frac{10}{12} = \frac{5}{6}.$

Addition: Adding fractions is slightly harder, because we can only add like items together. Thus, to add two fractions together, we must ensure that the denominators are equal.

$\frac{2}{3} + \frac{4}{5} = \frac{2 \times 5}{3 \times 5} + \frac{4 \times 3}{5 \times 3} = \frac{10}{15} + \frac{12}{15} = \frac{10+12}{15} = \frac{22}{15}.$

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Easy Math Editor

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Markdown	Appears as
`italics` or `_italics_`	italics
`bold` or `__bold__`	bold
- bulleted - list	bulleted list
1. numbered 2. list	numbered list
Note: you must add a full line of space before and after lists for them to show up correctly
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`> This is a quote`	This is a quote
# I indented these lines # 4 spaces, and now they show # up as a code block. print "hello world"	# I indented these lines # 4 spaces, and now they show # up as a code block. print "hello world"

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Remember to wrap math in `$` ... `$` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$

Comments

I love it because I'm only in 6th grade and its really easy so is the other stuff

Keely Patch - 6 years ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$