Three consecutive even numbers have a sum of 66.

what is the least number?

Let the least number = n

Since they are consecutive even numbers, they must be two numbers apart each; (n+2) and (n+4) are the second and third consecutive numbers, respectively.

Now we must add them together, and set the equation equal to 66.
n + (n+2) + (n+4) = 66

Simplify this to be: 3n + 6 = 66
66-6 = 3n
60 = 3n
n = 20

This means that the least number is 20, the second number is 22, and the third number is 24. 

If the three numbers were all equal, each one would be  1/3  of 66 .
That's  22, so the numbers would be  22,  22,  and 22 .

If you simply take  2  away from the first number and add it to
the last one, then their sum doesn't change, but now you have
20,  22,  and  24 .