Solution:

98

Explanation : ab + a(a-1)
7 * 8 + 7(7-1)
= 56 + 42

Solution:

See the figure for the answer. Wasn't it a bit tricky?

Solution:

A
D
C
A
B

Solution:

The attached picture gives away the solution. If you can find another solution, do send us yours.

Solution:

Put one black rock in one sack and put all the rest in the other one. In such manner you will get about 3/4 probability of surviving.

Solution:

2 minutes (duration between 9:59 and 10:01)

Solution:

Although it looks complicated, the answer is simple. The password to his computer is JIGSAW.
1st letter of Jug = J
2nd letter of Birthdays = I
3rd letter of Fights = G
4th letter of Cars =S
2nd letter of Laptops = A
1st letter of Watch = W

Solution:

Move the coins as given in the figure and you will get the required result.

Solution:

prinka is 10, in a system that awards five for each vowel.

Solution:

Zouma is 3 and has two footballs.
Ake is 1 and has one football.
Kalas is 4 and has three footballs.
Aina is 2 and has four footballs.

Solution:

What must be kept in mind before you start calculating through any method is that the weights can be put on both the pans.

So the weights - 1, 3, 7, 12, 43, 76, 102

The oldest man that can be weighed using these weights is a man aged 122 years