What is the approximate value will come in place of the question mark(?) in the following questions?

Let N be the greatest number that will divide 1305, 4665 and 6905, leaving the same remainder in each case. Then sum of the digits in N is:

While solving a problem, by mistake, Anita squared a number and then subtracted 25 from it rather than first subtracting 25 from the number and then squaring it. But she got the right answer. What was the given number? 

Of the three numbers, the second is twice the first and it is also thrice the third. If the average of three numbers is 44, the difference of the first number and the third numbers is: 

If (x¹¹+1) is divided by (x+1), then the remainder is :

Direction : What value should come in the place of question mark (?) in the following questions?

283 ÷25x4 + 186 = ? 

0.8% of a number is 31, then find the number.

Direction : What value should come in the place of question mark (?) in the following questions?

$$ 68\sqrt?-826=262 $$