Ratios, Proportions, and Scale Factors

Front

What is a ratio?

Back

A ratio is a comparison of two quantities expressed as a fraction, indicating how many times one value contains or is contained within the other.

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal.

Front

What is a scale factor?

Back

A scale factor is a number that scales, or multiplies, some quantity. It is used to determine the size of an object in relation to another object.

Front

How do you find a missing side in similar figures?

Back

To find a missing side in similar figures, set up a proportion using the corresponding sides of the figures and solve for the unknown.

Front

If two triangles are similar, what can be said about their corresponding angles?

Back

If two triangles are similar, their corresponding angles are equal.

Front

If the scale factor from a small shape to a big shape is 2, what does this mean?

Back

This means that each dimension of the big shape is twice as long as the corresponding dimension of the small shape.

Front

What is the relationship between the perimeters of similar figures?

Back

The ratio of the perimeters of similar figures is equal to the ratio of their corresponding sides.

Front

How do 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.

Front

What does it mean for two figures to be similar?

Back

Two figures are similar if they have the same shape but not necessarily the same size, meaning their corresponding angles are equal and their corresponding sides are in proportion.

Front

If the ratio of blue to red is 7:4, what does this indicate?

Back

This indicates that for every 7 parts of blue, there are 4 parts of red.