Conditional formula to highlight cell which is equal to a +/- range of another cell

[boomtown25]

Hello everyone!
I am trying to format a cell to fill with a certain color (Green) if that cell value is within a +/- range of another cell (we can say A1 for argument).
To further explain, if cell A1 is "3", I want cell B1 to fill with the color green if the value of B1 is between 0 and 6. Any help is greatly appreciated!

 

[Tetra201]

Is this the CF rule that you need?

=AND(B1>=0,B1<=A1*2)