Time zones and world time

You learn what time it is in other countries by taking away or adding hours.

How to work it out

  1. Look at the time difference.
  2. To the west it is earlier: take away hours.
  3. To the east it is later: add hours.
day× 24hour× 60minute× 60second

A worked example

15:00 in the UK, New York is 5 hours earlier

  1. New York lies to the west: it is earlier there.
  2. Take the hours away from the time here.
  3. Work out: 15 − 5 = 10.
  4. In New York it is 10:00.
More examples

10:00 in the UK, Tokyo is 9 hours later

  1. Tokyo lies to the east: it is later there.
  2. Add the hours: 10 + 9 = 19.
  3. In Tokyo it is 19:00.

17:00 in the UK, Paris is 1 hour later

  1. Paris lies to the east: add 1 hour.
  2. Work out: 17 + 1 = 18.
  3. In Paris it is 18:00.

Try it yourself

  1. Type the time (for example 14:00)

    In the UK it is 11:00. In Sydney it is 10 hours later. What time is it there?

  2. Type the time (for example 14:00)

    In the UK it is 13:00. In Tokyo it is 9 hours later. What time is it there?

Watch out

  • You add hours for a city to the west, when it is earlier there.

    Remember: to the west is earlier (take away hours), to the east is later (add hours).

Tips

  • West is earlier (minus hours), east is later (plus hours).

Why it works

Because the earth spins, the sun rises at a different time everywhere. The earth is split into time zones. To the west it is earlier, and to the east it is later.