International time zones

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International time zones
The zones are approximately 15º wide and are 1
hour apart. (They do vary from country to
country. For example Australian Central Standard
Time is GMT 9½h rather than GMT 9h. New
Zealand is in 1 time zone GMT 12h rather than
the two it should be in) The International
Date Line, IDL, is approximately opposite
Greenwich, but it is not a straight line. The
line deviates through the pacific and between the
USA and USSR. During daylight saving clocks are
moved forward by 1 hour.
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Example 1
Eliza leaves Sydney (GMT 10h) at 9am and flies
to Perth (GMT 8h). If the flight takes 5½h, what
is the local time when she lands?
Steps 1) Work out the time difference between
the 2 locations 2) Work out the local time at
the destination 3) Add the time of flight to
find the local landing time
As the 2 cities are on of the Greenwich
meridian to find the time difference.
the same side
subtract
1000 ? 0800
0200
As Perth is of Sydney the time difference.
west
subtract
0700
0900 ? 0200
Add the time of flight
0700 0530 ?Eliza lands at 1230pm Perth time.
1230
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Example 2
Tim leaves Buenos Aires (GMT ?3h) at 7pm Friday
and flies to Dacca (GMT 6h). If the flight takes
14h, what is the local time when he lands?
1) Work out the time difference between the 2
locations 2) Work out the local time at the
destination 3) Add the time of flight to find the
local landing time
As the 2 cities are on of the Greenwich
meridian to find the time difference.
different sides
add
0900
0300 0600
As Dacca is of Buenos Aires the time
difference.
east
add
2800 0400 Saturday
1900 0900
Add the time of flight
0400 1400 ?Tim lands at 6pm Saturday Dacca
time
1800
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Example 3
Imogen leaves Reykjavik (GMT ?1h) at 4am Monday
and flies to Anchorage (GMT ?9h). If the flight
takes 11½h, what is the local time when she lands
if Anchorage is using daylight saving time?
1) Work out the time difference between the 2
locations 2) Work out the local time at the
destination 3) Add the time of flight to find the
local landing time 4) Add time for daylight saving
As the 2 cities are on of the Greenwich
meridian to find the time difference.
the same side
subtract
0900 ? 0100
0800
As Anchorage is of Reykjavik the time
difference.
west
subtract
?0400 2000 Sunday
0400 ? 0800
Add the time of flight
2000 1130
3130 0730 Monday
Add 1h for daylight saving
0730 0100
0830
?Alisha lands at 830am Monday Anchorage time.
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Todays work
Exercise 7-05 Page 270 ? 272 Q1 ? 4, 10, 13, 14
21 Just for fun Q16, 17, 19 22
Fridays work
Exercise 7-04 Page 265 ? 266 Q1 ? 5, 7 ? 10, 12
? 15 17