Which operation could we perform in order to find the number of milliseconds in a year?

- 60 60 24 7 365
- 1000 60 60 24 365
- 24 60 100 7 52
- 1000 60 24 7 52?

**Answer:** 1000 60 60 24 365. 1 year = 365 days = 1000 * 60 * 60 *24 *365 ms

## Explanation

We need to determine the number of milliseconds in a year.

First of all, “milli” means thousandth and thus one second contains 1000 milliseconds.

**1 s = 1000 ms**

Next, there are 60 seconds in one minute and thus the number of milliseconds in a minute is then obtained by multiplying the number of milliseconds in a second by the number of seconds in a minute.

**1 min = 60 s = 1000 * 60 ms**

Next, there are 60 minutes in one hour and thus the number of milliseconds in an hour is then obtained by multiplying the number of milliseconds in a minute by the number of minutes in an hour.

**1 h = 60 min = 1000 * 60 * 60 ms**

Next, there are 24 hours in a day and thus the number of milliseconds in a day is then obtained by multiplying the number of milliseconds in an hour by the number of hours in a day.

**1 day = 24 h = 1000 * 60 * 60 * 24 ms**

Finally, we assume that there are 365 days in a year (assuming no leap years). The number of milliseconds in a year is then obtained by multiplying the number of milliseconds in a day by the number of days in a year.

**1 year = 365 days = 1000 * 60 * 60 * 24 * 365 ms**

We then note that the correct operation is 1000 60 60 24 365.