Float Sum. Workaround for the Java Script 0.3 billion 0004 error

Question

I’m making a list of exercises about Java Script and the question where you ask

05) Dealing with numbers in Javascript can give you a lot of headache.
Have you seen what happens when you do the following command on the console: console.log(0.1 + 0.2); The result will be: 0.30000000000000004.
Another important thing to note is the fact that the point is used in place of the comma and vice versa.
With this, we will do a simple exercise to show money always in the right way. Develop a Javascript function for it to receive a value like 0.30000000000000004 e return R$0,30 (note the comma and the dot)."

I got an intuitive solution that solved what was:

function reais(valorQuebrado){
        return `R$:${Math.floor(valorQuebrado)},${Math.floor(100 * valorQuebrado)}`
}

console.log(reais(0.30000000000000004))
console.log(reais(0.2 + 0.1))

However, the solution of the exercises gave me another type of solution that was:

function formatarValorDecimal(valorDecimal) {
    valorEmReais = `R$ ${valorDecimal.toFixed(2).toString().replace(".", ",")}`
    console.log(valorEmReais)
}

formatarValorDecimal(0.1 + 0.2)

I would like to know if there is a difference between the answers, or if my answer does not reach the general cases, so it could be a future code error.