A constant search before calls, flights, and live sport. This page has 100 important questions and answers. Original explainer for daily search — not a government login or live tracker.
Earth is split into time zones so noon is roughly when the sun is high locally. UTC (Coordinated Universal Time) is the baseline. A city at UTC+5:30 (India) is 5 hours 30 minutes ahead of UTC. Daylight saving time (DST) shifts clocks in some countries in summer — not in India, not in most of Arizona, and not on a fixed global date.
Live sport listings that say “7:30” without a zone are useless. Write IST, GMT, ET, or AEST.
100 important questions. Quick 10 is a random set; Full set plays every question.
Your score
100 questions and answers
Each item is a 4-option MCQ. Open a question, tap A–D. Green is correct, red is wrong. Original explainers — not copied match reports.
1. Pacific Time in US winter is usually
Tap A, B, C or D.
Answer: C) UTC−8
In PDT it becomes UTC−7.
2. A country can skip a day or repeat a day when
Tap A, B, C or D.
Answer: C) it jumps the date line by law (rare, historic cases exist)
Samoa 2011 is the usual textbook jump.
3. Noon local is only roughly solar noon because
Tap A, B, C or D.
Answer: B) zones are wide and DST shifts the clock
The clock is a social tool.
4. When in doubt for a global call, write
Tap A, B, C or D.
Answer: B) the time in UTC plus each main city
Nobody has to guess.
5. The official source for “time zones explained” (learn desk, item 1) is
Tap A, B, C or D.
Answer: D) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
6. The official source for “time zones explained” (learn desk, item 2) is
Tap A, B, C or D.
Answer: B) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
7. The official source for “time zones explained” (learn desk, item 3) is
Tap A, B, C or D.
Answer: A) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
8. The official source for “time zones explained” (learn desk, item 4) is
Tap A, B, C or D.
Answer: B) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
9. The official source for “time zones explained” (learn desk, item 5) is
Tap A, B, C or D.
Answer: A) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
10. The official source for “time zones explained” (learn desk, item 6) is
Tap A, B, C or D.
Answer: C) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
11. The official source for “time zones explained” (learn desk, item 7) is
Tap A, B, C or D.
Answer: D) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
12. The official source for “time zones explained” (learn desk, item 8) is
Tap A, B, C or D.
Answer: A) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
13. The official source for “time zones explained” (learn desk, item 9) is
Tap A, B, C or D.
Answer: B) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
14. The official source for “time zones explained” (learn desk, item 10) is
Tap A, B, C or D.
Answer: B) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
15. The official source for “time zones explained” (learn desk, item 11) is
Tap A, B, C or D.
Answer: A) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
16. The official source for “time zones explained” (learn desk, item 12) is
Tap A, B, C or D.
Answer: C) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
17. The official source for “time zones explained” (learn desk, item 13) is
Tap A, B, C or D.
Answer: D) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
18. The official source for “time zones explained” (learn desk, item 14) is
Tap A, B, C or D.
Answer: C) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
19. The official source for “time zones explained” (learn desk, item 15) is
Tap A, B, C or D.
Answer: D) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
20. The official source for “time zones explained” (learn desk, item 16) is
Tap A, B, C or D.
Answer: B) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
21. The official source for “time zones explained” (learn desk, item 17) is
Tap A, B, C or D.
Answer: A) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
22. The official source for “time zones explained” (learn desk, item 18) is
Tap A, B, C or D.
Answer: D) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
23. The official source for “time zones explained” (learn desk, item 19) is
Tap A, B, C or D.
Answer: C) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
24. The official source for “time zones explained” (learn desk, item 20) is
Tap A, B, C or D.
Answer: C) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
25. The official source for “time zones explained” (learn desk, item 21) is
Tap A, B, C or D.
Answer: D) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
26. The official source for “time zones explained” (learn desk, item 22) is
Tap A, B, C or D.
Answer: B) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
27. The official source for “time zones explained” (learn desk, item 23) is
Tap A, B, C or D.
Answer: A) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
28. The official source for “time zones explained” (learn desk, item 24) is
Tap A, B, C or D.
Answer: B) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
29. The official source for “time zones explained” (learn desk, item 25) is
Tap A, B, C or D.
Answer: A) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
30. The official source for “time zones explained” (learn desk, item 26) is
Tap A, B, C or D.
Answer: C) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
31. The official source for “time zones explained” (learn desk, item 27) is
Tap A, B, C or D.
Answer: D) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
32. The official source for “time zones explained” (learn desk, item 28) is
Tap A, B, C or D.
Answer: A) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
33. The official source for “time zones explained” (learn desk, item 29) is
Tap A, B, C or D.
Answer: B) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
34. The official source for “time zones explained” (learn desk, item 30) is
Tap A, B, C or D.
Answer: A) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
35. The official source for “time zones explained” (learn desk, item 31) is
Tap A, B, C or D.
Answer: B) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
36. The official source for “time zones explained” (learn desk, item 32) is
Tap A, B, C or D.
Answer: D) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
37. The official source for “time zones explained” (learn desk, item 33) is
Tap A, B, C or D.
Answer: C) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
38. The official source for “time zones explained” (learn desk, item 34) is
Tap A, B, C or D.
Answer: D) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
39. The official source for “time zones explained” (learn desk, item 35) is
Tap A, B, C or D.
Answer: C) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
40. The official source for “time zones explained” (learn desk, item 36) is
Tap A, B, C or D.
Answer: A) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
41. The official source for “time zones explained” (learn desk, item 37) is
Tap A, B, C or D.
Answer: B) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
42. The official source for “time zones explained” (learn desk, item 38) is
Tap A, B, C or D.
Answer: C) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
43. The official source for “time zones explained” (learn desk, item 39) is
Tap A, B, C or D.
Answer: D) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
44. The official source for “time zones explained” (learn desk, item 40) is
Tap A, B, C or D.
Answer: A) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
45. The official source for “time zones explained” (learn desk, item 41) is
Tap A, B, C or D.
Answer: B) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
46. The official source for “time zones explained” (learn desk, item 42) is
Tap A, B, C or D.
Answer: D) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
47. The official source for “time zones explained” (learn desk, item 43) is
Tap A, B, C or D.
Answer: C) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
48. The official source for “time zones explained” (learn desk, item 44) is
Tap A, B, C or D.
Answer: D) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
49. The official source for “time zones explained” (learn desk, item 45) is
Tap A, B, C or D.
Answer: C) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
50. The official source for “time zones explained” (learn desk, item 46) is
Tap A, B, C or D.
Answer: A) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
51. The official source for “time zones explained” (learn desk, item 47) is
Tap A, B, C or D.
Answer: B) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
52. The official source for “time zones explained” (learn desk, item 48) is
Tap A, B, C or D.
Answer: C) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
53. The official source for “time zones explained” (learn desk, item 49) is
Tap A, B, C or D.
Answer: D) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
54. The official source for “time zones explained” (learn desk, item 50) is
Tap A, B, C or D.
Answer: C) the authority or standard named on this page’s explainer
GKSchools English practice is original — not an official script.
55. UTC is
Tap A, B, C or D.
Answer: A) the world time standard clocks refer to
GMT is close in everyday talk; leap seconds are a UTC detail.
56. If London is UTC+0 in winter, New York (ET) is usually
Tap A, B, C or D.
Answer: B) UTC−5
In US DST, Eastern is UTC−4.
57. India Standard Time is
Tap A, B, C or D.
Answer: B) UTC+5:30 year-round
India does not use DST.
58. Crossing east usually means
Tap A, B, C or D.
Answer: D) local clocks jump forward (you lose hours in the day)
Jet lag is the body catching up.
59. A meeting at 09:00 PT for a London colleague is
Tap A, B, C or D.
Answer: D) afternoon in the UK (usually 17:00 GMT/BST)
Name the zone in the invite.
60. The International Date Line
Tap A, B, C or D.
Answer: C) is where the calendar date changes as you travel
It zigzags around islands.
61. AEST is often
Tap A, B, C or D.
Answer: C) Australian Eastern Standard Time (UTC+10)
AEDT is the daylight-saving version.
62. A fixture “tonight” without a city
Tap A, B, C or D.
Answer: D) is ambiguous — add a zone
Broadcasts sell the wrong click if they skip this.
63. In the simple classroom model, Earth is split into zones about
Tap A, B, C or D.
Answer: D) 15 degrees of longitude wide (one hour)
Politics then bends the lines.
64. GMT in everyday talk is close to UTC, but UTC is
Tap A, B, C or D.
Answer: A) the civil time standard with leap-second detail
Schedules should still name a zone.
65. Springing forward for DST means
Tap A, B, C or D.
Answer: B) clocks jump ahead and that night is shorter
Autumn/fall does the reverse where DST exists.
66. China uses one civil time,
Tap A, B, C or D.
Answer: A) UTC+8 for the whole country
The west of China sees a late sunrise on the clock.
67. Nepal Standard Time is a famous offset of
Tap A, B, C or D.
Answer: C) UTC+5:45
Not every zone is a whole hour.
68. Newfoundland, Canada, is often
Tap A, B, C or D.
Answer: A) UTC−3:30 (and −2:30 in DST)
Half-hour and 45-minute offsets exist.
69. Zulu time on flight plans means
Tap A, B, C or D.
Answer: C) UTC
A time ending in Z is UTC.
70. ISO 8601 style 14:00+05:30 means
Tap A, B, C or D.
Answer: A) 2pm in a zone 5 hours 30 minutes ahead of UTC
The offset is written beside the clock.
71. If city A is UTC+5:30 and city B is UTC−5, A is ahead of B by
Tap A, B, C or D.
Answer: A) 10 hours 30 minutes
Add the gaps from UTC.
72. The IANA time-zone database names zones like
Tap A, B, C or D.
Answer: D) America/New_York rather than a single fixed offset forever
DST rules change; names stay stable.
73. A calendar invite should state
Tap A, B, C or D.
Answer: B) the zone or a city, not only 7:30
Phones then convert for each guest.
74. Crossing the International Date Line eastward usually
Tap A, B, C or D.
Answer: C) repeats or drops a calendar date depending on direction
Westward and eastward are not the same date effect.
75. Line Islands / Kiritimati can sit near
Tap A, B, C or D.
Answer: B) UTC+14, among the first places into a new date
They see New Year early.
76. Baker or Howland Island style UTC−12 is
Tap A, B, C or D.
Answer: B) among the last civil offsets
Few people live there.
77. Jet lag is worse when you
Tap A, B, C or D.
Answer: D) cross many zones quickly, especially east
The body clock trails the wall clock.
78. UTC does not observe
Tap A, B, C or D.
Answer: B) daylight saving time
Countries add DST on top of a standard offset.
79. Arizona mostly stays on
Tap A, B, C or D.
Answer: A) Mountain Standard Time without statewide DST (exceptions exist)
The Navajo Nation is a known exception inside AZ.
80. When the US is on EDT, Eastern is
Tap A, B, C or D.
Answer: C) UTC−4
Winter Eastern Standard is UTC−5.
81. BST (British Summer Time) is
Tap A, B, C or D.
Answer: A) UTC+1
Winter UK is GMT, UTC+0.
82. AEST is UTC+10; AEDT is often
Tap A, B, C or D.
Answer: B) UTC+11
Not all Australian states use daylight saving.
83. A live match listed as 7:30 with no city is
Tap A, B, C or D.
Answer: D) ambiguous for a world audience
Add IST, GMT, or ET.
84. Unix timestamps count seconds from
Tap A, B, C or D.
Answer: A) an epoch defined in UTC (1970-01-01)
Servers usually store UTC, then display local.
85. A flight of 8 hours leaving at 22:00 local may land
Tap A, B, C or D.
Answer: C) the next calendar morning even if the clock says an earlier hour
Write both local times plus UTC if it matters.
86. Call a London morning meeting for California as
Tap A, B, C or D.
Answer: C) late evening the day before in California, or pick overlap hours
Name both zones in the title.
87. The equator does not
Tap A, B, C or D.
Answer: D) set time zones; longitude and law do
Noon is about the sun, zones are political too.
88. A country can choose an offset that does not
Tap A, B, C or D.
Answer: C) match its solar noon (Spain, China are examples people cite)
Convenience and history win over astronomy.
89. 15:00 UTC is the same instant as
Tap A, B, C or D.
Answer: A) 20:30 in India (IST)
IST is UTC+5:30.
90. Hawaii is typically
Tap A, B, C or D.
Answer: A) UTC−10 and does not use DST
It stays behind the US mainland.
91. A dual-time world clock is useful because
Tap A, B, C or D.
Answer: B) offsets and DST both move
Do not memorise last year chart.
92. The date line zigzags so that
Tap A, B, C or D.
Answer: C) island groups can share a date with their capital
It is not a straight 180° meridian in practice.
93. UTC+0 in winter London versus UTC+1 in Paris means
Tap A, B, C or D.
Answer: C) Paris clocks read one hour later
EU neighbours are not always the same zone.
94. A sports broadcaster should convert from
Tap A, B, C or D.
Answer: D) the venue local time, then label each feed
Fans in two continents otherwise arrive an hour late.
95. Midnight crossing during a chat means
Tap A, B, C or D.
Answer: C) one side may already be on the next calendar date
Write the date as well as the hour.
96. Military local offsets are sometimes lettered; J is skipped so that
Tap A, B, C or D.
Answer: C) J means local time of the observer, not a fixed zone
Z is Zulu / UTC.
97. A 24-hour clock on tickets reduces
Tap A, B, C or D.
Answer: D) am/pm mix-ups across zones
Still print the city.
98. If you travel west, your day gets
Tap A, B, C or D.
Answer: B) longer on the clock for that travel day
Eastbound, you lose hours in that day.
99. Software should store instants in UTC and
Tap A, B, C or D.
Answer: D) convert for each user display zone
That avoids double-shift bugs.
100. A meeting at 09:00 in Tokyo (UTC+9) is in London winter (UTC+0)
