Need help with % complete formula

Hi everyone. I am trying to calculate the % complete for a document. See attached. The started approach has a 10% weight age, approaches complete has an 80% weight age, and signed-off has a 10% weight age.

Example 1:

I have started an approach and 2/8 approaches are complete. The document has been signed-off also.

The % complete calculation should be: 10% + (80/8) *2 + 10% which equals 40% complete (cell E2).

Example 2:

I have started an approach and 4/8 approaches are complete. The document has not been signed-off.

The % complete calculation should be: 10% + (80/8) *4 which equals 50% complete (cell E2).

What should the formula for cell E2 be? Thanks a lot for your help guys.

thank you!!