What is the coolest letter in the alphabet?

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.

Replace The Question Mark Below With the Correct Number.

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

A cat, a dog and a monkey were stolen. 3 suspects got caught: Harish, Manoj and Tarun. All we know is each person stole one animal, but we do not know who stole which. Here are the investigation statements. Harish said: Tarun stole the cat. Manoj said: Tarun stole the dog. Tarun said: They both were lying. I did not steal the cat or the dog. Later on, the police found out the man who stole the monkey told a lie. The man who stole the cat told the truth. Can you find out who stole which?

Below is the sum of symbols in each row and column in the figure. Analyzing the figure, can you find out the value of the symbols?

How many triangles are there on the puzzle below?

Can you arrange four 9's and use at most 2 math symbols, to make the total 100?

I can write cow in 13 letters.

Can You?

Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

They came out at night, without being called.
They lost at day, without being stolen.
Who are they?