How to randomly select a number from a set of numbers?

I am trying to make a function which returns a random number from among a set of specified numbers (comma seperated) in React. I mean,

randomInside(10,20,25,45) // desired output is one of the numbers, e.g. 25

My try was:

const randomInside = (numbers) => {
    const array = [numbers]
    const newIndex = Math.floor(Math.random() * array.length)
    return array[newIndex]
}

but this gives the first item in all occurences. How can I fix this?

You need to collect all arguments into an array if you want to handle it as such. One way of doing so would involve the "rest" parameter ...:

console.log(randomInside(10,20,25,45)) // desired output is taking one of the numbers, i.e 25

function randomInside(...array){
  const newIndex = Math.floor(Math.random() * array.length)
  return array[newIndex]
}