Australia has three standard time zones. Eastern (AEST, UTC+10) covers Qld, NSW, Vic, Tas and the ACT. Central (ACST, UTC+9:30) covers SA and the NT. Western (AWST, UTC+8) covers WA. The sun rises in the east first, so eastern clocks are ahead. Find the difference from the UTC numbers, then add it going east or take it away going west. In summer NSW, Vic, Tas, the ACT and SA use daylight saving: their clocks go forward 1 hour. Qld, the NT and WA do not change.
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Move the hands
3:00
The short hand moves between hour numbers as the minutes pass. One full turn of the long hand is sixty minutes.
Words to know
- time zone
- a region where everyone uses the same clock time
- UTC
- the world's reference time that zones are measured from
- daylight saving
- moving clocks forward 1 hour in summer
Worked examples
It is 3:00 pm in Sydney in June. What time is it in Perth?
- 1.AEST is UTC+10 and AWST is UTC+8: Perth is 2 hours behind.
- 2.3:00 pm − 2 hours.
= 1:00 pm
It is 2:00 pm in Brisbane in June. What time is it in Darwin?
- 1.AEST is UTC+10 and ACST is UTC+9:30: Darwin is 30 minutes behind.
- 2.2:00 pm − 30 minutes.
= 1:30 pm
It is 10:00 am in Perth in January. What time is it in Sydney?
- 1.Sydney is usually 2 hours ahead of Perth.
- 2.In January Sydney is on daylight saving and Perth is not, so the gap is 3 hours: 10:00 am + 3 hours.
= 1:00 pm
For parents
Method: East is ahead: find the difference, then add or take away
What to say: Is the other city east or west? How many hours apart are the zones today?
Common mistakes:
- Moves the time the wrong way: adds when the other city is behind, or takes away when it is ahead.
- Ignores the extra half hour in Central time, as if the difference were only whole hours.
- Uses the standard-time difference in summer, forgetting that some states move their clocks forward.
- Applies daylight saving the wrong way, moving clocks back an hour instead of forward.
- Assumes neighbouring time zones are always exactly one hour apart.