1 press ctrl-a ©g dear 2009 – not to be sold/free to use time zones stage 6 - year 12 general...
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Press Ctrl-APress Ctrl-A©G Dear 2009 – Not to be sold/Free to use
Time ZonesTime ZonesStage 6 - Year 12Stage 6 - Year 12
General MathematicsHSC
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Time Zone (1/9)
Map
Time zones are calculated in relation to GMT.Greenwich Mean Time
For locations to our east we add time.
SydneyAdelaide9am
Sydney =Adelaide + 30min= 9am + 30min= 9:30 am
9:30am
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Time Zone (1/9)
Map
Time zones are calculated in relation to GMT.Greenwich Mean Time
For locations to our east we add time.
For locations to our west we subtract time.
PerthAdelaide
9am
Perth =Adelaide – 1hr 30min= 9am - 1hr 30min= 7:30 am
7:30am
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Time Zone (2/9)
Map
If it is 7:08am [07:08 hrs]
hours in London …
… what time isit in Sydney?
Sydney =London + 10hr [East]= 07:08 + 10hr= 17:08= 5:08 pm
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Time Zone (3/9)
Map
If it is 10:20am [10:20 hrs]
hours in Sydney …
… what time isit in Honolulu?
Honolulu =Sydney - 20hr [West]= 10:20 - 20hr= -10:20+ 24:00= 14:20 yesterday
= 2:20 pm yesterday
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Time Zone (4/9)
Map
If it is 10:20am [10:20 hrs]
hours in Sydney …
… what time isit in Honolulu?
Honolulu =Sydney + hr [East]= 10:20 + 4 hr [Crossing ‘Date Line’
subtract one day]= 14:20= 2:20 pm yesterday
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Time Zone (5/9)
Map
When crossing the International Date Line…
•going east – subtract one day
•going west – add one day
When determining time zones
1o in longitude equals 4 minutes.
15o in longitude equals 1 hour.