Quantitative Aptitude · Reasoning

Time and Clocks

562 Questions

Time and clocks problems evaluate quantitative aptitude by testing concepts on clock gains, losses, and relative speeds of hands. Questions also cover global time zones and standard time calculations. These logical reasoning topics frequently appear in SSC and banking exams.

Clock gain or lossTime zonesAngle between handsStandard time calculationPrecise time measurement

Time and Clocks Questions

Multiple choice technology programming languages

time_t t; Which one of the following statements will properly initialize the variable t with the current time from the sample above

  1. t = ctime();

  2. time( &t );

  3. t = localtime();

  4. t = clock();
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

time(&t) correctly initializes t with the current time. The time() function takes a pointer to a time_t variable and stores the current time there. Option B is correct. ctime() converts a time value to a string, localtime() converts to local time structure, and clock() returns processor time used - none of these initialize t directly.

Multiple choice

The following are the starting and ending times of activities A, B, C, D, E, F, G and H respectively in chronological order: “as bs cs ae ds ce es fs be de gs ee fe hs ge he”. Here, xs denotes the starting time and xe denotes the ending time of activity X. We need to schedule the activities in a set of rooms available to us. An activity can be scheduled in a room only if the room is reserved for the activity for its entire duration. What is the minimum number of rooms required?

  1. 3

  2. 4

  3. 5

  4. 6
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Multiple choice

The following are the starting and ending times of activities A, B, C, D, E, F, G and H respectively in chronological order: “as bs cs ae ds ce es fs be de gs ee fe hs ge he”. Here, xs denotes the starting time and xe denotes the ending time of activity X. We need to schedule the activities in a set of rooms available to us. An activity can be scheduled in a room only if the room is reserved for the activity for its entire duration. What is the minimum number of rooms required?

  1. 3

  2. 4

  3. 5

  4. 6
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Multiple choice

When it is 12.00 noon at Delhi (770 10' E), people at another place on earth take their 60'Clock morning tea. The longitude of that place is

  1. 170 30' E

  2. 12050 W'

  3. 1720 30' E

  4. 900 W
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Delhi is at 77°10' E. 6:00 AM is 6 hours behind 12:00 PM noon. Since Earth rotates 360° in 24 hours, each hour represents 15° of longitude (360/24 = 15). To go back 6 hours in time, we move 6 × 15 = 90° west. Starting from 77°10' E and moving 90° west gives 12°50' W. Option B shows 12°50' W (the formatting has the apostrophe misplaced but indicates the correct position).

Multiple choice

Very small time intervals are accurately measured by the

  1. Pulsars

  2. Quartz Clocks

  3. Atomic Clocks

  4. White dwarfs
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Atomic clocks use the frequency of atomic vibrations (typically cesium-133) to measure time with extreme precision - accurate to within one second in millions of years. They are far more precise than quartz clocks or astronomical methods.

Multiple choice

How many minutes for each degree of longitude does the local time of any place vary from the Greenwich time?

  1. Two minutes

  2. Four minutes

  3. Six minutes

  4. Eight minutes
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Earth completes one full rotation (360°) in 24 hours (1440 minutes), so each degree of longitude corresponds to 4 minutes of time difference (1440 ÷ 360 = 4). This is why places 15° apart have exactly 1 hour time difference, and the 180° meridian is 12 hours from Greenwich.

Multiple choice

15 minutes before 12:00 noon is

  1. 12:15 pm

  2. 11:45 pm

  3. 11:45 am

  4. 12:15 am

  5. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This is the right answer.

15 minutes before 12:00 noon is 11:45 am.

Multiple choice

2 hour 10 minutes is same as

  1. 90 minutes

  2. 70 minutes

  3. 130 minutes

  4. 100 minutes

  5. 120 minutes
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This is the right answer.

2 hour 10 minutes is same as 130 minutes. As one hour contains 60 minutes then two hours will have 120 minutes plus 10 minutes is equal to 130 minutes.

Multiple choice

22.45 hrs denotes:

  1. 9:45 pm

  2. 10:45 am

  3. 10:45 pm

  4. 22:45 pm

  5. 11:45 pm
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This is the right answer.

22:45 means 10:45 pm.

If we have to write 10:45 pm in 24 hrs clock then we will write it as 22.45 hrs.