Solution:

118119

Explanation:
Number are generated as below
1 2
3 4
1 x 4 + 2 = 6 , 2 x 3 + 1 = 7 => 67

3 4
5 6
3 x 6 + 4 = 22, 4 x 5 + 3 = 23 = 2223

5 6
7 8
5 x 8 + 6 = 46, 6 x 7 + 5 = 47 = 4647

7 8
9 10
7 x 10 + 8 , 8 x 9 +7 = 7879

Based on above pattern, desired number will be calculated as :
9 10
11 12
9 x 12 + 10 = 118, 10 x 11 + 9 = 119 = 118119

Solution:

Both 3 and 4th

Explanation:
- The water in tank1 will get filled up to the connectivity of tank1 and the tank2 and then it will start flowing to tank2.
- The water in tank2 will get filled up to the connectivity of tank2 and the -tank3 and then it will start flowing to tank3.
- The water in tank3 will get filled up to the connectivity of tank2 and the tank3 and then it will start flowing to tank3.
- As the outlet of tank3 and inlet of tank4 are not at the same level, water will continue to fill tank3 till the inlet of tank4.
- Now both the tank3 and tank4 fill simultaneously until both fill together.

Solution:

The code is 645
Explanation :
A) From Clues 1st and 2nd we know that one 9 is not in the code
B) From Clue 2nd we know that 9 3 and 8 are part of code
C) From Clue 3rd we know that 4 and 6 are part of code
D) From Clue 5th we know that 1 and 2 are not part of the code as we know 6 is part of the code and just 1 of 3 numbers is part of code.
E) From Clue 4th we know that 5 is also in the code as 8 and 1 are not part of code.

So the code is: 645

Solution:

They are all anagrams of time-related words.

1. CHARM: MARCH
2. DYNAMO: MONDAY
3. YAM: MAY
4. REAY: YEAR
5. EAR: ERA
6. ONE: EON
7. TOADY: TODAY

Solution:

73

Explanation:
It's a very famous puzzle known as "Josephus Problem Puzzle". It can be solved in various ways but the trick to solve this problem is illustrated below.

Binay number of 100 is: 1100100
complement pf 100 is 0011011, whose decimal equivalent is 27.
The desired answer will be 100 - 27 = 73

Solution:

GPUZZLES IS BEST PUZZLE SITE

Explanation:
Ascii value of 71 is: G
Ascii value of 80 is: P
Ascii value of 85 is: U
Ascii value of 90 is: Z
Ascii value of 90 is: Z
Ascii value of 76 is: L
Ascii value of 69 is: E
Ascii value of 83 is: S
Ascii value of 32 is:
Ascii value of 73 is: I
Ascii value of 83 is: S
Ascii value of 32 is:
Ascii value of 66 is: B
Ascii value of 69 is: E
Ascii value of 83 is: S
Ascii value of 84 is: T
Ascii value of 32 is:
Ascii value of 80 is: P
Ascii value of 85 is: U
Ascii value of 90 is: Z
Ascii value of 90 is: Z
Ascii value of 76 is: L
Ascii value of 69 is: E
Ascii value of 32 is:
Ascii value of 83 is: S
Ascii value of 73 is: I
Ascii value of 84 is: T
Ascii value of 69 is: E

Solution:

A = B = K =6
C =7
D = H = 1,
E=0 ,
F = I = G = 4,
J=3,
L=5

Now we can rewrite the equations as :
66 = 76 - 10
44 = 60 - 14
16 = 64 - 46
37 = 67 - 30
35 = 53 - 16
10 = 74 - 64

Solution:

120 km

Solution:

NUMBER +
NUMBER
=======
PUZZLE

Above puzzle can be solved by substituting
N - 2
U - 0
M - 1
B - 6
E - 8
R - 9
P - 4
Z - 3
L - 7

The puzzle can now be read as:

201689 +
201689
----------
403378

Solution:

A Leak.