slight math problem sorry

Ok guys I know this is a programming site and my problem is math but I don't know any math sites,

Therefor I'm asking for your help my problem is.

give your answer as fraction or decimal as appropriate.

where A = 4t + h

t + h

find A when t = 2 and h=3.

Now from what I remember I can answer this as a fraction or a decimal but I can't remember which is appropriate and why. I'm given the answer as 2.2 (a decimal) and not a fraction why not a fraction or why is a fraction not appropriate.

thanks for your help (leaner wanting to ba a master).