In a class of 180, when girls are twice the number of boys, Rupesh (a boy) ranked 34 ^thfrom top. If there are 18 girls ahead of Rupesh, how many boys are after him in rank?

The specified digits are 8, 2 and 9. Now, we know a perfect square number does not have 8 and 2 at unit's place. Therefore, we can make only two three-digit numbers from it, i.e., 829 and 289. Among these two numbers, 289 is a perfect square number, i.e., square of 17. Thus, unit's digit is 7 and ten's digit is 1.

Four times 3 present together with 2 and 7, where 2 and 7 present either side of 3.
1 1 1 1 3 3 2 2 [2 3 7] 7 3 3 3 6 6 4 [7 3 2] 4 9 8 7 [7 3 2] 3 3 3 4 4 [2 3 7]

If the day before yesterday was Saturday, then today is Monday.
Thus, tomorrow will be Tuesday and day after tomorrow will be Wednesday.

Given that :- 1st March is Saturday.
Other Saturdays in March = 8, 15, 22, 29
Therefore, 1st April = Saturday + 3 days = Tuesday

Given that :- Today is Wednesday + 2 days = Friday
Therefore, Day after tomorrow will be Sunday.

According to question,
Fifteen children are standing in a row facing north.
Left Side Position 1st, 2nd, 3rd, 4th, 5th, 6th, 7th, 8th, 9th, 10th, 11th, 12th, 13th, 14th, 15th Right Side position
Ravi is is eighth from the left end.
Left Side Position 1st, 2nd, 3rd, 4th, 5th, 6th, 7th, 8th, 9th, 10th, 11th, 12th, 13th, 14th, 15th Right Side position
......................................................................................Ravi
Ravi is to the immediate left of Prabha.
Left Side Position 1st, 2nd, 3rd, 4th, 5th, 6th, 7th, 8th, 9th, ........10th, 11th, 12th, 13th, 14th, 15th Right Side position
......................................................................................Ravi, Prabha
Arjun is second from the right end.
Left Side Position 1st, 2nd, 3rd, 4th, 5th, 6th, 7th, 8th, 9th, ........10th, 11th, 12th, 13th, 14th, 15th Right Side position
......................................................................................Ravi, Prabha........................................Arjun

8th, 9th, 14th
Ravi Prabha Arjun

According to the question,
Rajnish is older than Rajesh and Raman.
Rajnish > Rajesh, Raman..........(i)
Ramesh is older than Rajesh but younger than Rajeev.
Rajeev > Ramesh > Rajesh........(ii)
Raman is older than Rajeev.
Raman >Rajeev.......................(iii)
Combining all, we get
Rajinish > Raman > Rajeev > Ramesh > Rajesh

According to question,
If the positions of the first and the fifth digits of the number 83721569 are interchanged.
After interchange the new number = 13728569
similarly, the positions of the second and the sixth digits are interchanged.
Again after interchange the new number = 15728369

New arrangement of numbers is as follows: 15728369
Hence, third number from right end is 3.

According to question,
In a row of boys Akash is fifth from the left
Left 1 - 2 - 3 - 4 - Akash - 6 - 7 - 8 - 9 - 10 - 11 - 12 .................................................................................................................. Right
If Akash is twenty-fifth from the right then
Left 1 - 2 - 3 - 4 - Akash - 6 - 7 - 8 - 9 - 10 - 11 - 12 - 13 -14 - 15 -16 -17 -18 -19 - 20- 21- 22 - 23- 24- 25 -26 -27 -28 - 29 Right
Nikhil is eleventh from the right.
Left 1 - 2-3 -4 - Akash - 6 -7- 8- 9-10 -11-12- 13-14- 15 -16-17-18 - Nikhil -20-21-22 - 23 - 24 - 25-26 -27- 28- 29 Right

There are (25 ? 11? 1) = 13 boys between Akash and Nikhil.

According to given question,
If the positions of the first and the sixth digits of the group of digits 3 5 9 7 2 8 0 1 6 4 are interchanged.
New number after interchange = 8 5 9 7 2 3 0 1 6 4
Then the positions of the second and the seventh digits are interchanged.
New number after interchange = 8 0 9 7 2 3 5 1 6 4

After interchanging the number becomes as follows: 8 0 9 7 2 3 5 1 6 4

fourth digit from the right end after the rearrangement : 5