Answer: Option A. -> Monday
350 days, $$\frac{{350}}{7}$$ = 50, no odd days, so it will be a Monday.

Answer: Option A. -> Sunday
Formula : (Date + Month code + No.of years + No.of leap year + Century code)/7
$$\eqalign{
& = \frac{{24 + 0 + 11 + 2 + 6}}{7} \cr
& = \frac{{43}}{7} \cr
& = 1 \cr
& = {\text{Sunday}} \cr} $$

Answer: Option C. -> Friday
Given that first day of a normal year was Friday
Odd days of the mentioned year = 1 (Since it is an ordinary year)
Hence First day of the next year = (Friday + 1 Odd day) = Saturday
Therefore, last day of the mentioned year = Friday

Answer: Option A. -> Monday
22 Apr 2222 = (2221 years + period from 1-Jan-2222 to 22-Apr-2222)
We know that number of odd days in 400 years = 0
Hence the number of odd days in 2000 years = 0 (Since 2000 is a perfect multiple of 400)
Number of odd days in the period 2001-2200
= Number of odd days in 200 years
= 5 x 2 = 10 = 3
(As we can reduce perfect multiples of 7 from odd days without affecting anything)
Number of odd days in the period 2201-2221
= 16 normal years + 5 leap years
= 16 x 1 + 5 x 2 = 16 + 10 = 26 = 5 odd days
Number of days from 1-Jan-2222 to 22 Apr 2222
= 31 (Jan) + 28 (Feb) + 31 (Mar) + 22(Apr) = 112
112 days = 0 odd day
Total number of odd days = (0 + 3 + 5 + 0) = 8 = 1 odd day
1 odd days = Monday
Hence 22 Apr 2222 is Monday

Answer: Option D. -> Sunday
$$\eqalign{
& \frac{{10 + 4 + 96 + 24 + 0}}{7} \cr
& = \frac{{134}}{7} \cr
& = 1 \cr
& = {\text{Sunday}} \cr} $$

Answer: Option B. -> 111
Number of days from 26-Jan-1996 to 15-May-1996 (both days included)
= 6(Jan) + 29(Feb) + 31 (Mar) + 30(Apr)+ 15(May)
= 111

Answer: Option A. -> Sunday
94 days = (13 × 7) + 3 = 3 odd days.
The required day is 3 days beyond Thursday i.e., Sunday

Answer: Option B. -> Saturday
Counting the years 1600 + 300 + 74
In 1600 years, there are zero odd days
In 300 years, there is one odd day
In 74 years, there are 18 leap years and 56 normal years, so the odd days are:
18(2) + 56(1) = 36 + 56 = 92,
Which is 13 weeks and 1 odd day
In 25 days of January, 1975, there are 3 weeks and 4 odd days
Total odd days = 0 + 1 + 1 + 4
six odd days, so it was a Saturday.

Answer: Option B. -> Tuesday
20th June, 1837 means 1836 complete years + first 5 months of the year 1837 + 20 days of June
1600 years give no odd days
200 years give 3 odd days
36 years give (36 + 9 ) or 3 odd days
Thus 1836 years give 6 odd days
From 1st January to 20th June there are 3 odd days
Odd days: January 3, February 0, March 3, April 2, May 3, June 6 = 17
Thus the total number of odd days = 6 + 3 or 2 odd days
This means that the 20th of June fell on 2nd day commencing from Monday.
The required day was Tuesday.

Answer: Option D. -> Saturday
Clearly it can be understood from the question that 9 days ago was a Thursday
Number of odd days in 9 days = 2 (As 9 - 7 = 2, reduced perfect multiple of 7 from total days)
Hence today = (Thursday + 2 odd days) = Saturday