Keyboard words are not in alphabetical order, Why?

Replace The Question Mark Below With the Correct Number.

2 {38} 3
4 {1524} 5
6 {3548} 7
8 {????} 9

At a party, there are five people and a whole round cake lying at the centre of the table. Only four people will make a cut and take their piece and the last one will get the remaining piece on the table. How can they make sure that everyone gets a 1/5th of the piece?

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

Explain how?

Two boys were admitted to a school. When the headmaster asks them about their parents, they tell him that they have same parents (father and mother). On further inquiry, it turns out that they both share the same date for their birthday.

"Are you twins," ask the headmaster.
"No," replies the boys.

Is it possible?

Can you think of a smallest +ve number such that if we shuffle the digits of the number, the new number becomes double the original number?

I am quite hot but become too cold if you remove the first two letters. What am I?

When can we add 2 to 11 and get 1 as the correct answer?

If I put in one bird per cage, I have one bird too many. If I put in two bird per cage, I have one cage too many. How many cages and birds do I have?

Find the next number in the following series:
6, 14, 26, 98, __?