Replace the question mark with the number below given a simple math problem.

Place the numbers from 1 to 9 in the circles in a manner that each side of the triangle sums up to 17.

John and Jenni are a married couple. They have two kids, one of them is a girl. Assume safely that the probability of each gender is 1/2.
What is the probability that the other kid is also a girl?

Hint: It is not 1/2 as you would first think.

A swan sits at the center of a perfectly circular lake. At an edge of the lake stands a ravenous monster waiting to devour the swan. The monster can not enter the water, but it will run around the circumference of the lake to try to catch the swan as soon as it reaches the shore. The monster moves at 4 times the speed of the swan, and it will always move in the direction along the shore that brings it closer to the swan the quickest. Both the swan and the the monster can change directions in an instant.
The swan knows that if it can reach the lake's shore without the monster right on top of it, it can instantly escape into the surrounding forest.

How can the swan successfully escape?

Can you fill the blank with the correct number?

6 30 870 756030 _____

Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?

What number should come in place of the question mark below?

John bought 150 chocolates but he misplaced some of them. His Father asked him how many chocolates were misplaced.
He gave the following answer to him:
If you count in pairs, one remains
If you count in threes, two remain
If you count in fours, three remain
If you count in fives, four remain
If you count in sixes, five remain
If you count in sevens, no chocolate remains.

Can you analyze the statements and tell us how many chocolates were lost?

A man says, "Brothers and sisters, have I none, but that man's father is my father's son." Who is that man?

Find the next number in the series?
2, 12, 36, 80, 150, 252, 392, _ ?