NUMBERS, DISTANCE AND SPACE

> Assume there are 7 billion (7*10^9 = 7000000000) people on Earth.

Assumption entered.

> Assume the distance between Earth and the Moon to be 384400 km.

Assumption entered.

> Assume every human is exactly 1.5 m long with arms fully extended.

Assumption entered.

> Calculate, how many times would a "chain of humans" 
suprass the distance to the Moon?

Working....

A chain of humans would measure 1.5*7*1e9 = 10500000000 meters,

which is 10500000000/1000 = 10500000 km,

so it would be 10500000/384400 = 27.315296566077 times

The answer to your inquiry is:

If every human 1.5 m long kept each other at arms full length 
in a chain, the length of that chain would be equal to a little 
more than 27 times the distance form Earth to the Moon.