In a competitive exam, each correct answer could win you 10 points and each wrong answer could lose you 5 points. You sat in the exam and answered all the 20 questions, which were given in the exam.
When you checked the result, you scored 125 marks on the test.

Can you calculate how many answers given by you were wrong?

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.

It comprises roots which nobody sees,
Much taller than those trees,
Up and up it goes,
Still it never grows?

I have a five and a three-gallon jar. Assuming there is an infinite supply of water, how can I measure one-gallon water?

I am a five-letter word and people eat me. If you remove the first letter I become an energy form. If you remove the first two letters, I am needed to live. Scramble the last three letters and I am a drink. What word am I?

I purchased an awesome ice cream cone having 5 different flavour scoops.
Five flavours are pistachio, mint-chip, strawberry, marshmallow, and raspberry

I will give u some clues so that you can figure out the order of flavours from bottom to top.
1. The bottom flavour of the cone has 10 letters.
2. The marshmallow scoop is between the pistachio and the mint-chip scoop.
3. marshmallow is the raspberry scoop but below the mint-chip scoop.

So can you figure out the flavour of ice cream in order from bottom to top?

There is something which is always coming but never arrives?

What has many keys but can’t open a single lock?

Can you identify the direction in which this bus is moving; left or right?

Hint: The bus is moving on the roads of London.

A wooden log balances equally on the scales when weighed with three-quarters of a pound and three-quarters of a wooden log.

Can you calculate the weight of the entire wooden log?