The sum of five consecutive integers is 75. what is the third number?

Hi,

Let us assume those 5 integers are:

a-2, a-1, a, a+1, and a+2.

I have intentionally chosen the numbers this way to have a simple and useful sum of them, see below.

Their sum is: a-2 + a-1 + a + a+1 + a+2 = 5a = 75, therefore a = 15, which is exactly the 3rd number.

Green eyes. 

people went from manufacturing one object at a time by hand to manufacturing many objects in factories