JavaScript - Generate random number (range)

JavaScript : random number range

function randomRange(minVal, maxVal, floatVal) {
    var randVal = minVal+(Math.random()*(maxVal-minVal));
    return typeof floatVal=='undefined'?Math.round(randVal):randVal.toFixed(floatVal);
}

floatVal - optional, without it, the function will return an integer; it represents the number of decimal points; precision