JS: Calcular el promedio de una serie de números

<script>
const converge = (converger, fns) => (...args) => converger(...fns.map(fn => fn.apply(null, args)));

const average = converge((a, b) => a / b, [
  arr => arr.reduce((a, v) => a + v, 0),
  arr => arr.length
]);

varAux = average([1, 2, 3, 4, 5, 6, 7]); // 4 (28/7)
console.log(varAux);
varAux = average([3, 4, 5, 6, 7]); // 5 (25/5)
console.log(varAux);

varAux = average([1, 1, 1, 2, 3, 3]); // 1,833 (11/6)
console.log(varAux);
</script>