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 a figure.

Front

How do you calculate the perimeter of a shape using a scale factor?

Back

To find the perimeter of a scaled shape, multiply the original perimeter by the scale factor.

Front

If a model is built at a scale of 1 inch : 5 feet, how do you find the actual size from the model size?

Back

Multiply the model size by the scale factor to find the actual size.

Front

What is the formula for the area of a rectangle?

Back

Area = length × width.

Front

If a rectangle has dimensions of 2 cm by 3 cm, what is its area?

Back

Area = 2 cm × 3 cm = 6 cm².

Front

What happens to the area of a shape when it is enlarged by a scale factor of 2?

Back

The area increases by a factor of 2² = 4.

Front

How do you find the new area of a rectangle when using a scale factor of 4?

Back

Multiply the original area by 4² (16) to find the new area.

Front

If a map has a scale of 1 cm = 10 km, how far apart are two cities that are 4 cm apart on the map?

Back

Actual distance = 4 cm × 10 km/cm = 40 km.

Front

What is the relationship between scale factor and dimensions of a shape?

Back

The dimensions of a shape are multiplied by the scale factor to find the dimensions of the scaled shape.

Front

If a triangle has a perimeter of 12 cm and is scaled by a factor of 3, what is the new perimeter?

Back

New perimeter = 12 cm × 3 = 36 cm.