Solution:

40 or 96

Explanation:
Solution A :
Add the rhs of the last line to the current line
1 + 4 = 5
5 + 2 + 5 = 12
12 + 3 + 6 = 21
21 + 8 + 11 = 40

Solution B :
RHS = 1ST NUMBER + (1ST NUMBER * 2ND NUMBER)
1 + (1 x 4) = 5
2 + (2 x 5) = 12
3 + (3 x 6) = 21
8 + (8 x 11) = 96

Solution:

==== 65 ==== 35 ====
== 34 === 31 === 4 ==
= 10 == 24 == 7 == -3 =

Solution:

developers=2, testers=5 and content-writters=13

Explanation:
Let the number of developers, testers, and content-writers are denoted by d, t, and c respectively.

From the given information we can write the following 2 equations;
d + t + c = 20 . . . . . . (1)
3d + 1.5t + 0.5c = 20 . . . . . (2)

Multiplying equation (2) by 2 we get;
6d + 3t + c = 40 . . . . . (2)

equation3 - equation 1
5d + 2t = 20

The unique solution with whole numbers is d = 2 & t = 5

Therefore from equation(1) we can find;
c = 13

developers=2, testers=5 and content-writters=13.

Solution:

2 Ways

Explanation:
1 + 2 + 34 + 56 + 7 = 100.
1 + 23 + 4 + 5 + 67 = 100.

Solution:

3

Explanation:
Possible matches
Chelsea vs Tottenham
Chelsea vs ManCity
Chelsea vs Arsenal
Chelsea vs Liverpool
Tottenham vs ManCity
Tottenham vs Arsenal
Tottenham vs Liverpool
ManCity vs Arsenal
ManCity vs Liverpool
Arsenal vs Liverpool

Therefore there is a total of 10 matches. After every match, 2 points were distributed between two teams as:
Case1: One of team wins:
Winning team will get 2 points.

Case2: Match ends up in a draw
Both teams will share a point.

Therefore 10*2 = 20 points should be the sum of all team points.

6 + 5 + 4 + 2 + ? =20
? = 3

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:

13 + 11 + 6 = 30

Explanation
The trick is that you just need to rotate '9' to form '6'.

Solution:

5 => FIVE

Half of five => Remove 2 letters out of 4 i.e Remove letter 'F' AND 'E'.
It remains, 'IV'
The Roman value of 'IV' is 4.

Solution:

There can be many solutions. Three such solutions are:
A) ((8 - 8)^8)!
B) sqrt(8) * sqrt(8)/8
C) (8*(8 - 8))!

Solution:

The equation can be solved by substituting
B = 7
A = 8
S = 8
E = 3
L = 5

Therefore the equation now looks as:
7483 +
7455
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14938
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