In don't understand how to work this problem out

80% of 22 can be written in the following ways:

1) 80% of 22 = 17.6

2) 0.8 x 22 = 17.6
The percentage is converted into decimal form.

3) 80/100 x 22 = 17.6
The percentage is converted into fraction form.

80/100 can be simplified to 4/5, and the point 3 can also be written as:

4) 4/5 x 22 = 17.6

Thus, following options have the same value as 80% of 22.
Option A. 80/100 ⋅ 22
Option D. 0.8 ⋅ 22
Option E. 4/5 ⋅ 22