Color Scale Conditional Formatting

Hi,
Need assistance on Color Scale Conditional Formatting

I want to use formula to define Minimum, Midpoint and Maximum in the color scale, but am not able to achieve it.

My Criteria are as follows;

Minimum: Less than equals to 50%

Midpoint: More than 50% less than 70%

Maximum: More than 70%

I need this formula for Accuracy column only.

Am aware of what you have done.
In your file I have added a screen shot which shows the 3 color scale and have filtered out formula.
What I want to understand is whether I can use formula or not. Because when I try using formula, I get an error note.