Prelude> 4.5 `mod` 1.25

<interactive>:1:4:
    Ambiguous type variable `a' in the constraints:
      `Integral a' arising from use of `mod' at <interactive>:1:4-8
      `Fractional a' arising from the literal `4.5' at <interactive>:1:0-2
    Probable fix: add a type signature that fixes these type variable(s)