Proportions and Scale Factor

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.

Front

How do you find the scale factor between two similar figures?

Back

To find the scale factor, divide the length of a side of one figure by the corresponding length of the other figure.

Front

If a rectangle has a length of 4 cm and a width of 2 cm, what is the scale factor if it is enlarged to a length of 8 cm?

Back

The scale factor is 2.

Front

What is the relationship between proportions and cross-multiplication?

Back

In a proportion, cross-multiplication can be used to determine if two ratios are equal.

Front

If 3/4 = x/12, what is the value of x?

Back

x = 9.

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.

Front

If a model car is 1/18 the size of a real car, what is the scale factor?

Back

The scale factor is 1:18.

Front

How can proportions be used in real-life situations?

Back

Proportions can be used in cooking, map reading, and in any situation where scaling is necessary.

Front

What is the formula for finding the area of a rectangle?

Back

Area = length × width.