Proportions

So what is a proportion?

Two ratio’s that are equivalent (mathematically) are proportions.

An Example:

A few more examples

This one is a little tougher, but if we take 24 (numerator on the right) and divide it by 4(numerator on the left) we get 6. Also if we take 30 (denominator on the right) and divide it by 5 (denominator on the left) we get 6 again. So this must be a proportion.

Techniques to solve proportions

It’s true we don’t always know if two ratios are proportional, so we have a few techniques we can try and test them.

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Other techniques

Sometimes it’s hard to try and break down some numbers, especially prime numbers.

However, since fractions are only division, we can undo it by multiplication. We can do this in a few ways.

1^ST WAY, TRY TO GET RID OF THE DENOMINATORS

WAY #2, CROSS MULTIPLY

MULTIPLICATION!!!!!

So, we multiply 6 * 91 = 546, and we multiply 7 * 78 = 546. Since 546 = 546, we have a proportion!!!

WAY #3, TRY TO TAKE THE BIGGER FRACTION AND DIVIDE IT BY THE SMALLER ONE

So why does this matter?

Because life is not easy, and you will encounter issues as you work and live. It’s important to know how to discover proportions because you may need to fill in the blank once in a while.

Also, you need it to pass this class.

Examples

Now try these

Surprise! There’s more!