How it works
The parts of an angle add up to the whole angle.
A straight line is 180 degrees. A full turn is 360 degrees.
To find a missing part, take the part you know from the whole.
Worked examples
A straight line
- A straight line is 180 degrees. One part is 120. Find the other part.
- The whole is 180.
- 180 − 120 = 60.
- So the answer is 60.
A full turn
- A full turn is 360 degrees. One part is 225. Find the other part.
- The whole is 360.
- 360 − 225 = 135.
- So the answer is 135.
A small part
- A full turn is 360 degrees. One part is 40. Find the other part.
- The whole is 360.
- 360 − 40 = 320.
- So the answer is 320.
A taste of the worksheet
These are the first problems of set A. The printable sheet has many more, with an answer key.
- A right angle is 90 degrees. One part is 60. Find the other part.
- An angle has two parts, 30 degrees and 60 degrees. How many degrees in all__
- An angle has two parts, 90 degrees and 30 degrees. How many degrees in all__