I think that I will have to do something along the lines of:

 if ($numerator > 7169 || $denominator > 1650){
          print "Do nothing";
          # Place another method in here
        }
        else {     
          my $fprob = Statistics::Distributions::fprob($numerator,$den
+ominator,0.025);
}
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The FINV function in Excel (equivalent to the fprob function in Statistics::Distributions) is able to go above the denominator and numerator values specified as limits here.