Solution:

Carriage

Explanation:
2Car + 3Carriage = 2 Bus ........(1)
2Car + 1Carriage = 1 Bus + 1Carriage ..... (2)
1 Bus + 1Car + 1Carriage = 3car + ?

From Statement 2 ,
2Car = 1Bus
From Statement 1 ,
2Car + 3Carriage = 2 Bus
1Bus + 3Carriage = 2 Bus
=> 3Carriage = 1Bus
Hence
The Carriage = 2, the Car = 3 and the Bus = 6

Solution:

3

Explanation:
1 + 2 + 3 + 4 + 5 => 15 => 5 - 1 =>4
4 + 5 + 6 + 7 + 8 => 30 => 3 - 0 =>3
6 + 7 + 8 + 9 + 11 => 41 => 4- 1 =>3

Solution:

6

Explanation:
Key1: 3 attempts for 3 gates.
Key2: 2 attempts for remaining 2 gates.
Key3: 1 attempts for the last gate.

Solution:

It can be done as shown below.

Solution:

11

Explanation:
Tzu‑ying won 3 games
V.Sindhu must win 3(to balance 3 games she lost) + 5 games(required for min 50$) = 8 games
Total Games = 3 + 8 = 11 games.

Solution:

A Clock

Solution:

19.

Note: Many of you have jumped to solution 21.

Solution:

Avengers

Explanation:
A + ven(Van) + G(google) + ers(ears)

Solution:

Cup-8

Explanation:
This might be tricky for mobile users where the bottom cup is difficult to focus on.

Solution:

12 Angry Men.