Scale Factor

Front

What is a scale factor?

Back

A scale factor is a number that scales, or multiplies, some quantity. It is used to enlarge or reduce figures in a proportional way.

Front

How do you calculate the new dimensions of a shape when using a scale factor?

Back

To calculate the new dimensions, multiply each original dimension by the scale factor.

Front

If a rectangle has dimensions of 3 cm by 5 cm and is enlarged by a scale factor of 2, what are the new dimensions?

Back

6 cm by 10 cm.

Front

What is the formula for the area of a rectangle?

Back

Area = length × width.

Front

If a rectangle with a scale factor of 3 has an area of 20 cm², what is the area of the original rectangle?

Back

The area of the original rectangle is 20 cm² / (3 × 3) = 20 cm² / 9 = 2.22 cm².

Front

What does it mean for two shapes to be similar?

Back

Two shapes are similar if they have the same shape but different sizes, and their corresponding angles are equal.

Front

How do you find the scale used on a map?

Back

To find the scale, divide the actual distance by the distance on the map.

Front

If 1 inch on a map represents 50 miles, how far apart are two cities that are 3 inches apart on the map?

Back

150 miles apart.

Front

What is the perimeter of a rectangle?

Back

Perimeter = 2 × (length + width).

Front

If a triangle has sides of lengths 5 cm, 12 cm, and 13 cm, what is its perimeter?

Back

The perimeter is 5 cm + 12 cm + 13 cm = 30 cm.