Parse int to double VueJS

I have a computed function in VueJS which calculates the sum of an array I got. However, it only returns Int numbers rounded to nearest number, even though I parseFloat. Can anyone help me out on this one?

data: {
        courses: [{Course: "A", Hours: "02.00"}, {Course: "B", Hours: "01.00"}]

 computed: {
        calculateAllHours: function (){
            return this.statistics.reduce((totalHours, course) => {
                let test = (totalHours) + parseInt(course.Hours)
                return parseFloat(test);

The result gives me 3, but I want to have 03:00 or 03.00