Explanation

Given:

Central angle = 180 degrees

1. Calculate the total angle of the pie graph:

The total angle of a pie graph is always 360 degrees since it represents the whole or 100% of the data.

2. Determine the proportion:

The proportion is the ratio of the given angle to the total angle of the pie graph.

In this case, it is 180 degrees divided by 360 degrees.

Proportion = 180 degrees / 360 degrees

Simplifying the division:

Proportion = 1/2

Therefore, the proportion of the central angle in the pie graph is 1/2, which can also be expressed as 50% or 0.5.