Australian time zones
Australia is divided into $3$3 time zones (shown in the map on the left). They are:
Eastern Standard Time (AEST): covering Queensland, New South Wales, Australian Capital Territory, Victoria and Tasmania.
Western Standard Time (AWST): covering Western Australia. ( $2$2 hours behind AEST)
Central Standard Time (ACST): covering South Australia, the Northern Territory. ( $\frac{1}{2}$12 an hour behind AEST)
The time zones become a bit more tricky during Daylight Savings because not all the states use it. Queensland, the Northern Territory and Western Australia stay on Standard Time. The map on the right shows that during Daylight Savings, Australia actually has $5$5 time zones!
Similar to Australia, Indonesia is divided into three time zones: Indonesia Western Time Zone (IWTZ), Indonesia Eastern Time Zone (IETZ), Indonesia Central Time Zone (ICTZ). Its neighbouring country Papua New Guinea has another time zone.
Practice questions
Question 1
Question 2
Complete the table to show the time in each time zone.
WST CST EST $\editable{}$$:$:$\editable{}$ $5$5$:$:$25$25 $\editable{}$$:$:$\editable{}$
$5$5$:$:$11$11 $\editable{}$$:$:$\editable{}$ $\editable{}$$:$:$\editable{}$ $\editable{}$$:$:$\editable{}$ $\editable{}$$:$:$\editable{}$ $12$12$:$:$25$25 $\editable{}$$:$:$\editable{}$ $7$7$:$:$17$17 $\editable{}$$:$:$\editable{}$
Question 3
If it is $16$16:$11$11 in Perth, what time would it be in Melbourne in 24 hour time?
Time Zones
| City | Time |
|---|---|
| Sydney | GMT+10 |
| Melbourne | GMT+10 |
| Adelaide | GMT+9: 3 0 |
| Perth | GMT+8 |
| Darwin | GMT+9:30 |
| Brisbane | GMT+10 |
| Hobart | GMT+10 |
| City | Time |
| Sydney | GMT+10 |
| Melbourne | GMT+10 |
| Adelaide | GMT+9:30 |
| Perth | GMT+8 |
| Darwin | GMT+9:30 |
| Brisbane | GMT+10 |
| Hobart | GMT+10 |
In Melbourne, it would be $\editable{}$:$\editable{}$.
Question 4
Indonesia is divided into three time zones: Indonesia Western Time Zone (IWTZ), Indonesia Eastern Time Zone (IETZ), Indonesia Central Time Zone (ICTZ). Its neighboring country Papua New Guinea has another time zone.
If it is $6$6:$16$16 am in IWTZ:
What time is it in ICTZ?
$\editable{}$:$\editable{}$ am
What time is it in IETZ?
$\editable{}$:$\editable{}$ am
What time is it in Papua New Guinea?
$\editable{}$:$\editable{}$ am
Daylight savings time (DST)
Daylight savings time (DST) is used by lots of countries, including Australia, New Zealand, the USA and the UK during their summers. In Australia, for daylight savings time, everyone moves their clocks forward one hour on the first Sunday in October, when the days are getting longer during Spring, and then they move the clocks back to the regular time on the first Sunday in April, when the days are getting shorter.
This means that during DST, our time zones are an extra hour ahead of the standard time zones.
Currently, Queensland, the Northern Territory and Western Australia do not use daylight savings.
Converting from standard to daylight savings time
Eastern Standard Time or Standard Time is abbreviated to AEST
Daylight Savings Time is abbreviated to AEDT
AEDT to AEST (daylight savings time to standard time) - subtract one hour
AEST to AEDT (standard time to daylight savings time) - add one hour
During daylight savings, clocks are moved forward $1$1 hour from the standard time, so $8$8 am standard time would be $9$9 am in daylight savings time, $6$6 pm AEST would become $7$7 pm AEDT and so on.
Similarly, when we go from daylight savings time to standard time, clocks are moved back $1$1 hour, so $12$12 pm AEDT would be $11$11 am AEST and $14:22$14:22 AEDT would be $13:22$13:22 AEST.
Practice questions
Question 5
When the time is $14$14$:$:$15$15 in Perth, what is the time in:
Sydney without DST?
$11$11$:$:$15$15
A$12$12$:$:$15$15
B$16$16$:$:$15$15
C$17$17$:$:$15$15
DSydney during DST?
$11$11$:$:$15$15
A$12$12$:$:$15$15
B$16$16$:$:$15$15
C$17$17$:$:$15$15
D
Question 6
If it is $14$14:$35$35 in Sydney in Eastern Standard Time, what time would it be in Daylight Savings Time?
$14$14:$35$35 AEST would be $\editable{}$:$\editable{}$ AEDT.
Question 7
If it is $16$16:$14$14 in Sydney in Daylight Savings Time, what time would it be in Eastern Standard Time?
$16$16:$14$14 AEDT would be $\editable{}$:$\editable{}$ AEST.