A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.

What is the next number in the series?

15 29 56 108 208 ?

Find The Missing Number In the Sequence.
6 25 64 ? 32 1

If,

6 / 7 = 2
3 / 9 = 7
8 / 2 = 6

Then

4 / 5 = ?

You need to pick one entry from pot A and one from pot B to have a perfect match. Can you do it?

There is an English word that can be used up to four times in a row without modifying the spelling and form a valid grammatical sentence.

Do you know what word is that?

A maths symbol is hidden in the below Bar Graph. Can you decipher it?

Use only one mathematical symbol and all numbers (0-9) to get a sum of 99

I have nine bottles of wine and one of the nine bottles is poisoned.
I need to find the poisoned bottle with two facts
(1) Poison is deadly, only a sip will cost death
(2) I have two mice to do so.

How should I do it?

Which five letter word can be added at the end of below word to form a
valid word?

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