As per the formula,
Average of the cubes os 1st 'n' natural numbers= n(n+1)2/4
where, n= 5.
? Required average = 5(5+1)2/4
= (5 x 36)/4 = 5 x 9= 45
Normally, hands of a watch coincide after 655/11 min.
So, loss per hour = 15/11 min
? Loss per day = 24 x 15/11 = 24 x 16/11
= 3410/11 min
Each day of the week is repeated after 7 days.
So, after 63 days, it will be Monday.
Hence, after 64 days. it will be Tuesday.
1992 being a leap year, it has 2 odd days. So, the first day of the year 1993 will be two days beyond Wednesday i.e., it will be Friday.
This being a leap year none of the next 3 year is a leap year. So, the day of the week will be 3 days beyond Monday i.e., it will be Thursday.
Angle traced by hour hand in 12 h = 360°
Angle traced by hour hand in 25/4 h = (360/12) x (25/4)° = 187.5°
Angle traced by minute hand in 60 min = 360°
Angle traced by it in 15 min = (360/60) x 15° = 90°
? Required angle = (187.5° - 90°) = 97.5°
Time from 7 am on a day to 6 am after 3 days is 95 h.
Now , 23 h 45 min of the clock in question = 24 h of correct clock
i..e., 95/4 h of the clock in question = 24 h of correct clock
? 95 h of the clock in question = (24 x 4/95 x 95) h of correct clock = 96 h
So, the correct time is 96 h from 7 am, Monday, ie., 7 am, Friday.
1600 years contains 0 odd day; 300 years conains 1 odd day. Also, 83 years contains 20 leap years and 63 ordinary years and therefore, (40 + 0) odd days i.e., 5 odd days.
? 1983 years contain (0 + 1 + 5) i.e., 6 odd days
Number of days from Jan. 1984 to 31st Oct 1984 = (31 + 29 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31) = 305 days = 4 odd days
? Total number of odd days = 6 + 4 = 3 odd days
So, 31st Oct 1984 was wednesday
First we look for the leap years during this period 1997, 1998, 1999 are not leap years.
1998 and 1999 together have net 2 odd days No. of days remaining in 1997 = 365 - 16 = 349 days = 49 week 6 odd days
January 4, 2000 gives 4 odd days.
? Total no. of days = 2 + 6 + 4 = 12 days = 7 Days (1 week) + 5 odd days
Hence, January 4, 2000 will be 5 days beyond Thursday i.e., it will on Tuesday.
Time from 7 am on Sunday to 7 pm on following Sunday
= 7 days 12 h = 180 h
? Watch gains (5 + 54/5) min or 54/5 in 180 h.
Now, 54/5 min are gained in 180 h.
? 5 min gained in (180 x 5/54 x 5) h = 83 h 20 min.
= 3 days 11 h and 20 min
? Watch is correct after 3 days 11 h and 20 min after 7 am of Sunday.
? It will be correct at 20 min past 6 pm on Wednesday.
Period upto 5th June, 2002 = (2001 yr + Period from 1.1.2002 to 5.6.2002)
? Odd days in 1600 yr = 0
Odd days in 400 yr = 0
Odd days in 1 ordinary year = 1
Odd days in 2001 year = (0 + 0 + 1) = 1
Number of days from 1.1.2002 to 5.6.2002
January + February + March + April + May + June
= 31 + 28 + 31 + 30 + 31 + 5
= 156 days = 22 weeks + 2 days
= 2 odd days
? Total number of odd days = (1 + 2) = 3
? The required day is Wednesday.
Comments
There are no comments.Copyright ©CuriousTab. All rights reserved.