Please HELP!! Giving wrong answers!

Okay I am trying to get Ms Excel to calculate the following function:
=(Q3-0.16)/(4.98-0.16) so I can use it to calculate a large number of data where initially Q3 = 0.16.

Surely 0.16-0.16/anything = zero, however, Ms Excel is calculating this to be 0.001014684!!

And also it is calculating the rest of my data wrongly using this formula???

Any ideas???? Is it because I have excel set in the wrong calculation mode?? How do I get around this?

Any help would be much appreciated!!!

Lloyd Owens