Quantitative Aptitude

Clocks and Calendars

428 Questions
All Angle between hands 150 Clock gaining or losing time 132 Clock hands coincidence 69 Right angle times 30 Find time from angle 21 Decoding mixed date formats 7 Find day using reference date 6 Repeating same calendar 6 Date without reference day 3

Clocks and Calendars Questions

Multiple choice

At what time between $7$ and $8$ o' clock will the hands of a clock be in the same straight line but, not together?
  1. $5$ min. past $7$
  2. $5\displaystyle\frac{2}{11}$ min. past $7$
  3. $5\displaystyle\frac{3}{11}$ min. past $7$
  4. $5\displaystyle\frac{5}{11}$ min. past $7$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

At 7 o'clock, the hands are 35 minute spaces apart. For them to be in a straight line but not together, they must be 30 minute spaces apart. The minute hand must gain 35 - 30 = 5 minute spaces. The time taken is 5 * (60/55) = 60/11 = 5 5/11 minutes past 7.

Multiple choice

Rajeev and Sanjeev are too close friends. Rajeev's watch gains $1$ minute in an hour and Sanjeev's watch loses $2$ minutes in an hour. Once they set both the watches at $12: 00$ noon, with my correct watch. When will the two incorrect watches of Rajeev and Sanjeev show the same time together?
  1. $8$ days later
  2. $10$ days later
  3. $6$ days later

  4. can't be determined
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Rajeev gains 1 min/hr and Sanjeev loses 2 min/hr. The relative difference is 3 min/hr. They will show the same time when the difference is 12 hours (720 minutes). Time = 720 / 3 = 240 hours. 240 hours / 24 hours/day = 10 days.

Multiple choice

A watch which gains $5$ seconds in $3$ minutes was set right at $7$ a.m. In the afternoon of the same day, when the watch indicated quarter past $4$ o'clock, then the true time is
  1. $4$ p.m.
  2. $59\dfrac {7}{12}$ minutes past $3$
  3. $58\dfrac {7}{11}$ minutes past $3$
  4. $2\dfrac {3}{11}$ minutes past $4$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The watch gains 5 seconds every 3 minutes. In 1 hour (60 minutes), it gains 5 * 20 = 100 seconds. From 7 a.m. to 4:15 p.m. is 9 hours and 15 minutes (9.25 hours). Total gain = 9.25 * (100/60) minutes = 9.25 * 1.666 = 15.416 minutes. 4:15 minus 15.416 minutes is 4:00 p.m.

Multiple choice

In a clock, what is the time period of meeting of the minute hand and the second hand?
  1. $59\ s$
  2. $\displaystyle \frac{60}{59}s$
  3. $\displaystyle \frac{59}{60}s$
  4. $\displaystyle \frac{3600}{59}s$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The minute hand moves at 0.5 degrees/min (or 1/120 deg/sec). The second hand moves at 6 degrees/sec. Relative speed = 6 - 1/120 = 719/120 deg/sec. Time to meet = 360 / (719/120) = 43200 / 719 seconds. This is approximately 60s, but the exact formula is 3600/59.

Multiple choice

A 12 dial clock has its minute hand defective.Whenever it touches dial 12, it immediately falls down to 6 instead of running smoothly (the hour hand remains unaffected during that fall). It was set right at 12 '0' clock in the noon. A clock is set to show the correct time at 11 a.m. The clock gains 12 minutes in 12 hours what will be the true time when the watch indicates 1 p.m. on the 6th day ?

  1. 10 a.m.

  2. 11 a.m.

  3. 12 noon

  4. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Multiple choice

At what time are the hands of a clock together between 5 and 6?
  1. $33\displaystyle \frac{3}{11}$ min. past $5$
  2. $28\displaystyle \frac{3}{11}$ min. past $5$
  3. $30$ min. past $5$
  4. $27\displaystyle \frac{3}{11}$ min. past $5$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The hands of a clock are together when the minute hand has gained 25 minute spaces on the hour hand. The formula is (60/55) * minutes. At 5 o'clock, the minute hand is at 0 and the hour hand is at 25. The time is 25 * (60/55) = 1500/55 = 300/11 = 27 3/11 minutes past 5.