i have thousands of letters?

A Post office

i have thousands of letters?

A Post office

Deck of cards.

No, he's still living!

1, 2 and 3

In the end, what is the expected number of loops (strings tied to their own end)?

Each time you tie two together the number of string ends available decreases by 2. The chance of grabbing a string and its end is 1/(2N-1).

What am I?

Wheelbarrow.

Elastic, because it stretches!

A train passes the platform in 36 seconds.

The train passes a man in 20 seconds.

The speed of the train is 54km/h.

Speed = Distance/Time

To convert km/h into m/s we multiply by 5/18

Convert speed into m/s

=> 54 x 5/18 = 15 m/s

The length of the train is:

=> 15 × 20 = 300 meter

Distance covered in 36 seconds

=> 36 x 15 = 540 meter

The length of the platform is:

=> 540 - 300 = 240 meter

The length of the platform is 240 meters

How will they cross?

What am I?

Path.

The bathroom light