For a conventional standard-definition television screen, the width-to-height…

Concept

An aspect ratio compares the width of a displayed image with its height and is written as width : height.

A value above 1 describes a frame wider than it is tall; a value below 1 describes a frame taller than it is wide.

Application

1. Interpret each offered ratio as width : height.

2. For the conventional standard-definition television format, take the frame width as 4 units and its height as 3 units.

3. Therefore, width : height = 4 : 3.

Cross-check and contrast

• 4 : 3 gives a width-to-height quotient of 4/3, approximately 1.33.

• 3 : 4 gives a width-to-height quotient of 3/4, or 0.75.

• 2 : 3 gives a width-to-height quotient of 2/3, approximately 0.67.

• 2 : 4 simplifies to 1 : 2 and gives a width-to-height quotient of 0.50.

Hence, the conventional standard-definition television aspect ratio is 4 : 3.