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At what time between 5 and 6 o'clock will the hands of a clock be 3 minutes apart?
In this type of problem, the formula is"
Here, H is replaced by the first interval of given time and t is spaces apart.
Given that H is 5.
mins or 24 mins
Therefore, the hands will by 3 minutes apart at 336/11 minutes or 24 minutes past 5.
In the year 1648, if February had 5 Sundays, then what was the day on February 13, 1750?
Since February had 5 Sundays in 1648, so February 1, 1648 was a Sunday.
So, number of odd days up to February 1, 1748 = 5
Number of odd days up to February 1, 1750 = (2 + 1) = 3
Number of odd days up to February 13, 1750 = 12
So, total number of odd days = 5 + 3 + 12 = 20
So, number of odd days from February 1, 1648 to February 13, 1750 = 6
Hence, the answer is 'Saturday'.
At what time between 4 o'clock and 5 o'clock will the hands of a clock be at a right angle?
Using formula, [where θ = angle between the hour-hand and the minute-hand, m - minutes, h - hours]
There will be 2 values.
minutes past 4 or m = minutes past 4.
At what time between 4:15 a.m. and 5:05 a.m. will the angle between the hour hand and the minute hand of a clock be the same as the angle between the hands at 8:45 p.m.?
Hour hand rotates 360° in 12 hrs, so it rotates 30° in 1 hour.
So, in 1 min, it rotates 0.5°.
Minute hand rotates 6° in 1 min.
So, angle at 8:45 = 0.25 × 30° = 7.5°
At 4:15, angle will be 0.25 × 30° + 30° = 7.5° + 30° = 37.5°
So, 37.5° + 0.5t + 7.5° = 6t
45 = 5.5t
Hence clock makes same angle at 23minutes past 4 o'clock
Alex turned a clock on at 3:00 pm. But the clock is defective, due to which it lags behind by 9 minutes after each day (24 hours). What will be the real time when the clock indicates 6:00 am on the 4th day of it's successive working?
Time from 3 pm on a day to 6 am after 4 days is 87 hours. Now, 23 hr 51 min on this clock are the same as 24 hr on the correct clock.
That is, on this clock = 24 hr on the correct clock
∴ 87 hr on this clock = hr on the correct clock
= 87 hr and 33 minutes approx. on the correct clock
So, the correct time will be 6:33 am.
If 15th March, 2013 was a Friday, then 10th July, 2013 will be a
Number of days from March 15th, 2013 to July 10th, 2013 = 16 + 30 + 31 + 30 + 10 = 117
On dividing 117 by 7, remainder is 5.
Now, counting 5 days after Friday, we get Wednesday.
At what time between 7 o'clock and 8 o'clock will the hands of a clock be in a straight line but not together?
How many days will there be from 23rd January, 2011 to 31st July, 2013 (both days included)?
As 2012 was a leap year, so the number of days in each month from 23rd January, 2011 to 31st July, 2013 is given as follows.
Since 2011 is not a leap year = 365 - 22 = 343 days
Number of days in 2012 = 366 days (leap year)
Number of days in 2013:
January = 31 days
February = 28 days
March = 31 days
April = 30 days
May = 31 days
June = 30 days
July = 31 days
Total number of days in 2013 = 212
Therefore, total number of days from 23rd January, 2011 to 31st July, 2013 = 343 + 366 + 212 = 921
Two clocks are set correctly at 10 a.m. on Friday. The first clock gains 2 minutes per hour, which is twice as much as gained by the second clock. What time will the second clock register when the correct time is 2 p.m. on the following Monday?
The time duration from 10 a.m. on Friday to 2 p.m. on the following Monday is 76 hours.
The clock gains 1 minute per hour.
∴ Time gained in 76 hours = 76 minutes = 1 hour 16 minutes
∴ Time shown by the second clock will be 3:16 p.m.
A man went outside between 7 o'clock and 9 o'clock at such a time that the minute hand and the hour hand were found to be coinciding before 8 o'clock; and when he returned, again he found both the hands to be coinciding, but after 8 o'clock. What was the time when he returned to the house?
He returned after 8 o'clock but before 9 o'clock, at such a time when both the minute hand and the hour hand were found to be coinciding.
In a simple way, we need to calculate the time when the angle between the minute hand and the hour hand is zero.
Angle between the minute hand and the hour hand at 8 o'clock = 8 × 30 = 240°
We can reduce the difference of 5.5 degree in 1 min,
Required time = 8 hrs + 240 × 2 ÷ 11
A clock gains 2 minutes in an hour and an other clock loses 4 minutes in an hour. If both these clocks were set at 8 a.m, what will be the time in the first clock, if the second clock shows 10 p.m?
In 1 hour, the first clock turns 62 minutes and the second 56 minutes. This implies that for every 56 minutes of the second clock, the first clock gains 6 minutes.
'The second clock shows 10 p.m.' means that it runs for 14 hours.
In this time, the first clock gains = 90 minutes.
So, the time will be 11:30 p.m.
At what time between 9 and 10 will the hands of a clock be together?
To be together between 9 and 10 o'clock, the minute hand has to gain 45 minute spaces.
55 minute space is gained in 60 minutes.
45 minute space will be gained in
At 49minutes past 9, the hands of the clock will be together.
What day of the week was it on 15th August, 1987?
15th August, 1987 means '1986 years + 7 months + 15 days'.
1600 years have 0 odd days, and 300 years have 1 odd day.
86 years contain 21 leap years and 65 ordinary years and therefore, 42 + 65 = 107 or 2 odd days.
1986 years give 0 + 1 + 2 = 3 odd days
Number of days from 1st January, 1987 to 15th August, 1987 = 31 + 28 + 31 + 30 + 31 + 30 + 31 + 15
= 227, i.e. 3 odd days
Total number of odd days = 3 + 3 = 6
The day on 15th August, 1987 was a Saturday.
How many times during a day will the hour hand and the minute hand of a clock be six minutes apart?
Note that at 1:00, the minute hand and hour hand are 5 minutes apart from each other. Then, between 1:00 and 2:00, only once, i.e. some time after 1:10, minute hand and hour hand will be 6 minutes apart from each other. Similarly, at 11:00, the minute hand and hour hand are 5 minutes apart from each other. Then, between 11:00 and 12:00, only once, i.e. some time before 11:50, minute hand and hour hand will be 6 minutes apart from each other. It can be observed twice that the hour hand and minute hand are 6 minutes apart from each other. Therefore, the answer is 44 times.
In a college, a 24-hour watch loses 5 minutes in 3 hours. If it is set correct on Tuesday midnight, then when will the watch show the correct time next?
The watch loses 5 minutes in 3 hours.
It loses 1 minute in (3/5) hours.
To show the correct time again, watch must create a 24-hour difference. (Since in one round, an hour-hand covers 24 hours.)
So, it loses 60 minutes in (3/5) × 60 hours or 36 hours.
It loses 24 hours in 36 × 24 hours or 864 hours or 36 days
Therefore, after exactly 36 days, the clock will show the correct time.
A clock shows the time as 6 am. If the minute hand gains 2 minutes every hour, then how many minutes will the clock gain by 9 pm?
We know that the clock gains 2 minutes every hour.
Number of hours between 6 am and 9 pm = Number of hours between 6 am and 12 noon + Number of hours between 12 noon and 9 pm
= 6 + 9 = 15 hours
Hence, in 15 hours, the clock will gain 15 x 2 = 30 minutes
A tutor teaches 8 days consecutively and then takes off on the ninth day. If he starts teaching on Monday, then on what day of the week will he get his 12th off day?
He teaches for 8 consecutive days and takes an off on the 9th day.
For each off day, 8 teaching days + 1 off day = 9 days passed
So, on the 12th off day, there are 9 x 12 = 108 days passed
We have to find the day of the week on 12th off day.
So, we have to deduct a day.
Number of odd days = (108 - 1)/7 = 107/7 = 2
He started teaching on Monday.
So, the 12th off day is Monday + 2 = Wednesday
I purchased some clocks from a second hand goods store. There were some problems in them. When the actual time passed 1 hour, the wall clock was 10 minutes behind it. When 1 hour was shown by the wall clock, the table clock showed 10 minutes ahead of it. When table clock showed 1 hour, the alarm clock was 5 minutes behind it. When alarm clock showed 1 hour, the wrist watch was 5 minutes ahead of it. Assuming that all clocks are correct with actual time at 12 noon, what will be shown by the wrist watch after 6 hours?
1. Table clock - Wall clock = +10 minutes ⇒ 1 hour in 6 hours
2. Alarm clock - Table clock = -5 minutes ⇒ 30 minutes in 6 hours
3. Wrist watch - Alarm clock = +5 minutes ⇒ 30 minutes in 6 hours
Also, every hour, wall clock loses 10 minutes.
If it is 6 hours since 12 noon, then time shown by the wall clock = 6:00 - 1 hour = 5:00 pm
⇒ Time shown by table clock with reference to wall clock = 5:00 + 50 min = 5:50 pm
⇒ Time shown by alarm clock with reference to table clock = 5:50 pm - 25 minutes - 25/6 minutes = 5:21 pm
⇒ Time shown by wrist watch = 5:21 + 25 minutes + 21/6 = 5.47 pm
Hence, 5.47 pm is the answer.
Today is Friday. A person wants to take a doctor's appointment. As the doctor is busy, he asks him to come three days after the day before the day after tomorrow. On which of the following days does the doctor ask the person to come?
Today is Friday.
Lets solve this problem in reverse order.
Then, we have day after tomorrow = Sunday
The day before the day after tomorrow = Saturday
Three days after the day which is before the day after tomorrow = Tuesday
Hence, Tuesday is the correct answer.
If the current time is 6:20, then after how much time will the hands of the clock make the same angle as they do at present?
Now, the angle is
If the angle between the hands is 70°, then the time can be found as follows.
M = 220/11 = 20 minutes or M =
So, the same angle will be made at 6:45
So, the required answer is 6:45- 6:20 = 25minutes