Allows for floating point math to be done in js

Floating point problem solver

function Num(v, precision) {
    this.val = v;
    var multiplier = Math.pow(10, precision || 3),
        // Helper fn, Makes a new num for chaining
        m = function(n) {
            return new Num(n, Math.log10(multiplier));
        }
    // pseduo operand overriding to allow for generic addition of nums
    this.valueOf = function() {
        return this.val * multiplier;
    }
    
    // Just in case
    this.getMultiplier = function() {
        return multiplier;
    }
    
    // All of the underscored methods return regular numbers
    this._add = function(num) {
        return (this.valueOf() + num) / multiplier;
    }
    
    this._subtract = function(num) {
        return this.add(num*-1);
    }
    
    this._multiply = function(num) {
        return (this.valueOf() * num) / (multiplier*multiplier);
    }
    
    this._divide = function(num) {
        return (this.valueOf() / num);
    }
    
    // These return Num objects
    this.add = function(num) { return m(this._add(num)); }
    this.subtract = function(num) { return m(this._subtract(num)); }
    this.multiply = function(num) { return m(this._multiply(num)); }
    this.divide = function(num) { return m(this._divide(num)); }

    return this;
}