Step by step
The question
Question: a circle graph has a 180° slice for pizza: what percent pizza?
pizza: 180°
Here is the slice.
180° of the 360° circle.
1 Angle over 360
The slice is 180 out of 360 degrees.
180 and 360 can both be divided by 180: 1/2.
= 180360 = 180 ÷ 180360 ÷ 180 = 12
Careful!
Degrees are out of 360, not out of 100.
Careful: not 180% ✗
2 As a percent
Percent means out of 100.
1/2 times 100% is 50%.
= 12 × 100% = 50%
3 Check
Let's check: 50% of 360 degrees is 180°, the slice.
So the answer is right!
50% of 360 = 180°
Let's look back.
First: angle over 360.
Then: as a percent.
Last: check.
Answer
= 12 × 100% = 50%