Which number should replace the question mark?

Below, you can see three complete equations and one incomplete. Based on the three complete ones, can you complete the incomplete one?

5 $ 4 $ 3 $ 9 = 4215
6 $ 9 $ 2 $ 6 = 3816
4 $ 7 $ 3 $ 3 = 1122
7 $ 2 $ 7 $ 4 = ____

A patient was diagnosed with some ailment. He was given five different tablets to take at night at an interval of 15 minutes.

How long will it take the patient to consume all the five tablets?

Too much grey makes things difficult. However, your task here is to find the elephant hidden in the picture.

There are two guys standing face to face in a room. On a wall, there is a clock. One of those is a prophet. He tells the other guy that he will be stabbed in the back in five minutes.

Shocked to hear that, the other guy stares at the clock. Just after the five minutes, he is stabbed on the back. Can you tell what happened?

There are are five things wrong with this sentence; only geniuses will be able to to spot all of the mitstakes

If,

Akriti = 631
Levis = 521
Sroti = 521
Aneel = 533
Then,
Sunil =?

Find the next number in the series.
1 10 24 43 67 ?

What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?

Decode below rebus
D
N
A
T
S , D