How to get an array of booleans as answer for a parameter "under 10"?

I want to evaluate whether the number is under than 10, having as an answer an array of booleans.
I tried using forEach, map, but I didn’t succeed in any attempt.

function underTen (arr){
  let underTenAnswer = arr.forEach(function(n){
    if (n < 10) {
      true;
    } else {
      false;
    }
  })
}

Input: underTen([1,9,12,19,4,16]
Expected outcome: Array [True, True, False, False, True, False]

I’m a beginner, sorry if something is notoriously incorrect.

>Solution :

There is a really quick way to do this:

let a = [1, 2, 3, 4, 5, 6, 7];
let b = [1, 2, 3, 4, 12, 8];

console.log(a.every((x) => x < 10)) // true
console.log(b.every((x) => x < 10)) // false

We use Array.every() here to check if each array element passes some condition.

If you need to return an array of booleans, then you can use Array.map():

let b = [1, 2, 3, 4, 12, 8];
console.log(b.map((x) => x < 10)) // [true, true, true, true, false, true]