Solving Proportions

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal. For example, if a/b = c/d, then a, b, c, and d are in proportion.

Tags

CCSS.7.RP.A.2A

Front

How do you solve a proportion?

Back

To solve a proportion, cross-multiply the terms. For example, if a/b = c/d, then you can solve for a by calculating a = (b * c) / d.

Tags

CCSS.7.RP.A.2C

Front

What is the cross-multiplication method?

Back

The cross-multiplication method involves multiplying the numerator of one ratio by the denominator of the other ratio. This is used to solve proportions.

Front

If 3/4 = x/12, what is x?

Back

x = (3 * 12) / 4 = 9.

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CCSS.3.NF.A.3B

CCSS.4.NF.A.1

Front

What is the definition of a ratio?

Back

A ratio is a comparison of two quantities by division. It can be expressed as a fraction, decimal, or percentage.

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CCSS.6.RP.A.1

CCSS.6.RP.A.2

Front

How can you express a ratio in simplest form?

Back

To express a ratio in simplest form, divide both terms of the ratio by their greatest common divisor (GCD).

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CCSS.6.RP.A.1

CCSS.6.RP.A.2

Front

What is a unit rate?

Back

A unit rate is a ratio that compares a quantity to one unit of another quantity. For example, if a car travels 300 miles in 5 hours, the unit rate is 60 miles per hour.

Tags

CCSS.6.RP.A.1

CCSS.6.RP.A.2

Front

If 5 apples cost $2, what is the cost of 1 apple?

Back

The cost of 1 apple is $2 / 5 = $0.40.

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CCSS.6.RP.A.1

CCSS.6.RP.A.2

Front

What is the relationship between proportions and similar figures?

Back

Proportions are used to describe the relationship between corresponding sides of similar figures, which have the same shape but different sizes.

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CCSS.8.G.A.2

CCSS.HSG.CO.B.6

Front

If a/b = c/d, what can you say about the cross products?

Back

The cross products are equal, meaning a * d = b * c.

Tags

CCSS.7.RP.A.2A