HackerRank Clocks and Calendars Quiz -1

We know that the formula find between the angel

x=(11/2min-30Hr)

(11/2 * 40 -30(3))

(220-90)

(130 deg).

sum of A.P. series=(n/2)(2*a+(n-1)*d)

here sum=13524,n=6,d=7

substituting these values in above eq.

solving we get a=1911

Firstly we find the day of 1 April 2001.So we can find it easily .

The last 2 digit of the year is 01

=> 01 divided by 4

=> So Quotient is 0

=> Then date is 1

=> the code of April is 6

=> the code of year is 6

Then added 01+0+1+6+6= 14

=>Now we will divide 14 to 7

So remainder is 0

So the day is Sunday.

If 1 April 2001 is Sunday then 4th April 2001 is Wednesday.

So Option D is Correct.

1/10th of an hour = 6 minutes

Let us start from Monday 10 am to friday 3.00 pm , total hours = 4 days 5 hrs(4*24+5 = 101 hrs).

Clock lose per hour = 6 min, so total time loses is 101 * 6minutes = 606 minutes (10 hrs 10 minutes ).

So actual time = Friday 3.00 pm + 10 hrs 10 minutes = saturday 1.10 am.

In a correct clock, the minute hand gains 55 min spaces over the hour hand in 60 min.

To be together again, the minute hand must gain 60 min over the hour hand.

We know that 60 min are gained in (60/55)×60 = 65(5/11)min

But they are together after 63 min. gain in 63 min = 65 – 63 = 2 = 65(5/11) - 63=2(5/11) = (27/11)min.

Gain in 24 hrs = = 27×60×24/11×63 = 56(8/77)min.

Lion speak lies on Monday,Tuesday,Wednesday;

Lion speak truth on Sunday,Thursday,Friday,Saturday;

 

Rat speak truth on Sunday,Monday,Tuesday,Wednesday;

Rat speak lie on Thursday,Friday,Saturday;

 

Suppose,Lion tells truth on thursday that Yesterday(Wednesday)

was one of the day which

he/she tells lies.

Then Rat tells lie on thursday that Yesterday(Wednesday) was one of the

day which he/she tells lies.

 

So Yesterday is Wednesday

Angle traced by hour hand in 12 hours = 360 °

Angle traced by hour hand in 1 hour = 360°/12 =30°

Angle traced by hour hand in 8 hour = 8 × 30° = 240°

At 8:30, hour hand will be in middle of 8 & 9, so angle traced by hour hand at 8:30

= 240° + (30°/2) = 240° + 15° = 255° -(i)

Angle traced by minute hand in 60 minutes = 360 °

Angle traced by minute hand in 1 minute  = (360°/60)= 6°

Angle traced by minute hand in 30 minutes = 30 × 6° = 180°  -(ii)

Now, the angle between the two hands of a clock when time is 8:30  = 255° - 180° (from i & ii)

= 75°

8th jan, 2029 = 2028 years + 1st jan to 8th jan (2029)

2028 years = 1600 year + 400 year + 28 year

 

1600 years = 0 odd days

400 years = 0 odd days

28 years = 0 odd days (28/7 = 0 remainder)

 

therefore, jan 2029 = 1 to 8 = 8 days = 1 odd day (8/7 = 1 remainder)

so, 1 odd day corresponds to MONDAY

after 12 o clock 12:21.......=1

from 1 to 9 it is 1.01, 1.11, 1.21, 1.31, 1.41, 1.51.= 6

similarly 2.02,2.12,.................

6*9=54+1=55

after 10 o clock 10:01, 11:11

Ans: 55+2=57

At 6 o'clock it barks 6 times so there are a total 5 time intervals. Total time taken = 30 sec

Hence, the time taken between any two consecutive consecutive = (30/5) = 6 seconds

Similarly, the clock will bark 12 times at 12 o’ clock.

At 12o’clock there will be 11 intervals.

Hence total time needed at 12 o’clock = 11 × 6 = 66 seconds