what does this picture(rebus) riddle means ?

Solve the counting riddle by identifying the number of triangles in the given picture.

What four weights can be used to balance from 1 to 30 pounds?

Through your logical capabilities, can you make 7 an even?

It is always ahead of me yet I can never see it. What is it?

Manish has to secure 40% marks to pass his B.tech final exams.
He got just 40 marks and failed by 40-marks.

What is the maximum marks?

There are people and strange monkeys on this island, and you can not tell who is who (Edit: until you understand what they said - see below). They speak either only the truth or only lies.
Who are the following two guys?
A: B is a lying monkey. I am human.
B: A is telling the truth.

By moving exactly three matchsticks can you make the below equation true.It can be solved by 3 ways.

There is one thing that goes round the house and also inside the house but never even share a brief touch. What is it?

On a bright sunny day, two fathers took their son fishing in the lake. Each man and son were able to catch one fish. When they returned to their camp, there were only three fishes in the basket. What happened?

PS: None of the fish were eaten, lost, or thrown back.