Solution:

10 = 9.9999999... .
The proof is correct and the fact is for real. There is no error in it.

Solution:

192

Explanation:
I started with the number 192.
Adding the reversed 291 to 192 gave me 483.
Similarly,
483 + 384 = 867
867 + 768 = 1635
1635 + 5361 = 6996

Solution:

3816547290

Solution:

4

Explanation:
Now if you go on calculating 2^300, you will lose so much time and it might not even be feasible to carry out so long of calculations. Thus we will make use of a trick here. We will calculate the remainder of each power of 2 till we come across a pattern.

2^1 divided by 4 leaves the remainder 2.
2^2 divided by 4 leaves the remainder 0.
2^3 divided by 4 leaves the remainder 0.
2^4 divided by 4 leaves the remainder 0.

You can see that all the following powers of two will be divisible by 4. Therefore the remainder when 2^300 is divided by 4 will be 0 only.

Solution:

The chances that the pair you take out is a white pair is zero.

Just analyze the statement carefully. If there are two colored socks in a drawer, there can be three chances if you take out a pair. It can be either black socks or white socks or a mixed of two. But as per the statement the chances of taking out a black pair of socks is 1/2. Therefore, only two chances exist. We do know that there is a mix of white and black socks in the drawer and thus the second chance has to be a mixture of them both. This is the reason why we can deduce that there are three black socks in the drawer and just one white sock. Thus the probability of taking out two white socks will be zero.

Solution:

146900

Explanation:
Whenever you face such type of questions, it is wise to begin from the last thing. Here in this question the last thing will be the 9th temple. He climbed down 100 steps and thus you know, he had Rs. 100 before beginning climbing down. Thus, he must have offered Rs. 100 to the god in that temple too (he offered half of the total amount). Also, he must have dropped Rs. 100 while climbing the steps of the ninth temple. This means that he had Rs. 300 before he begand climbing the steps of the ninth temple.

Now, we will calculate in the similar manner for each of the temples backwards.
Before the devotee climbed the eight temple: (300+100)*2 + 100 = 900
Before the devotee climbed the seventh temple: (900+100)*2 + 100 = 2100
Before the devotee climbed the Sixth temple: (2100+100)*2 + 100 = 4300
Before the devotee climbed the fifth temple: (4300+100)*2 + 100 = 8900
Before the devotee climbed the fourth temple: (8900+100)*2 + 100 = 18100
Before the devotee climbed the third temple: (18100+100)*2 + 100 = 36,500
Before the devotee climbed the second temple: (36500+100)*2 + 100 = 73300
Before the devotee climbed the first temple: (73300+100)*2 + 100 = 146900

Therefore, the devotee had Rs. 146900 with him initially.

Solution:

Yes it is possible in Roman Numerals. In Roman Numerals,
9 = IX
10 = X
11 = XI

Thus by removing one from 9, you are getting 10 and by removing one from 11, you are getting 10 again.

Solution:

There are three roses and four bees.

Solution:

1000

Solution:

No

Explanation:
7 is the only prime followed by a cube.
Assume that n3-1 is a prime for some n.
N3-1 will be equal to (n−1)(n2+n+1)
Now, n-1 divides n3-1.
If n-1>1, then we will have a contradiction to n3-1 being a prime.