var totalprices = function (count, price) { var count=count; var price=price; return (count * price).toFixed(2) } var sum = function (allPrice, discounts) { var allPrice=allPrice; var discounts=discounts; return (allPrice - discounts).toFixed(2) } var add = function(price = 0 ,prices = 0){ return (price+prices).toFixed(2); } var tofd = function(num,t_num = 2){ return num.toFixed(t_num) } var math = function(val){ return Math.abs(val) } module.exports = { totalprices: totalprices, sum:sum, add:add, tofd:tofd, math:math }