If you toss a coin 10 times and it lands heads up every time, what are the chances it will land heads up if you toss it again?

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

Three ants are sitting at the three corners of an equilateral triangle. Each ant starts randomly picks a direction and starts to move along the edge of the triangle. What is the probability that none of the ants collide?

In a concert, Christina is performing a dance show with her group.
At 10:00, she and her crew were dancing in an absolutely straight line. At that time Christina was standing in 4th position from both the front and back end of the row.

What was the size of her crew?

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.

Mother's Name is Mrs. SIXTY TWO
Son's Name is FIFTY TWO
Daughter's Name is FORTY TWO
What is Name of Father?

Which Number is the odd one out?

A) 7145
B) 2716
C) 5321
D) 4135

Can you find a pattern and the missing number in the series given below?

100, 155, 258,? , 584, 819.

How will you measure 15 minutes using two hourglasses of 7 minutes and 11 minutes respectively?

If,

A + B = C
D - C = A
E - B = C

Based on the above equations, find out the answer for:

D + F = ?