# write 2.158 radians in terms of Pi

#### yeny

##### New member
Hello, can someone show me how 2.158 radians can also be written as .687pi? I need to learn how to do this so I can write my answer in terms of pi as opposed to 2.158.

Yeny

#### topsquark

##### Well-known member
MHB Math Helper
Hello, can someone show me how 2.158 radians can also be written as .687pi? I need to learn how to do this so I can write my answer in terms of pi as opposed to 2.158.

It's just a change in scale. $$\displaystyle 2.158 \text{ rad } = \frac{ 2.158 \text{ rad } \pi }{ \pi} = \frac{2.158 \text{ rad }}{3.1415926535} \cdot \pi \approx 0.687 \pi \text{ rad }$$