round to the nearest tenth

Question

Please how to round to the nearest decimal tenth? Example : 0.56 => 0.5; 2.78 => 2.8

You can use `num.toFixed(1)`, although why does `0.56` get rounded to `0.5`? — Spectric, Aug 21 '22 at 16:26

score 4 · Accepted Answer · answered Aug 21 '22 at 16:34

4

Multiply by 10, then round then divide back by 10:

const round = (num) => Math.round(num * 10)/10

console.log(round(0.56))
console.log(round(2.78))

Then using the same logic, you can write a general rounding function:

const round = (num, decimal) => Math.round(num * 10**decimal)/10**decimal

console.log(round(5.142533564, 4))
console.log(round(62.5236, 2))

answered Aug 21 '22 at 16:34

Brother58697

1

Input => 0.56 ; Output => 0.5 – Mohamed Zahour Aug 21 '22 at 16:43
0.56 rounds up to 0.6. If you want it to only round down, replace `Math.round()` in my solution with `Math.floor()` – Brother58697 Aug 21 '22 at 16:47

1 Answers1