I have teeth but i don't bite. Who Am I ?

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?

Which number should replace the question mark?

10+10 and 11+11 can give you the same answer.

Explain how?

Replace the letters of words with a number so that the below equation holds true

BASE +
BALL
---------
GAMES
----------

John buys rice at Rs.60/kg from Britain and then sells them at Rs.5/kg in India. As a result of this, he becomes a millionaire. How come?

I am weightless, but you can see me. Put me in a bucket, and I'll make it lighter. What am I?

1. What does:
TIM JOB
represent?

2. What does:
MO_ _
represent?

Four cars come to a four-way stop, each coming from a different direction. They can’t decide who got there first, so they all go forward at the same time. All 4 cars go, but none crash into each other. How is this possible?

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