Question

The sum of three consecutive even numbers is 78. what is the first number

Answer 1

`x+(x+2)+(x+4)=78\\3x+6=78\\3x=78-6\\3x=72\\ \\x= (72)/(3) \\ \\x=24`

The first number is 24

Answer 2

This is a common algebra problem. Let us start by establishing the numbers. By the way, here is the theory behind the math.

If we call the first number
`n`, then the next consecutive even number is 2 away, so we will call it
`n+2`, and so forth, the 3rd number
`n+4`

Lets form an equation! We know that given the sum of the 3 consecutive even numbers is 78, the equation is:


`n+(n+2)+(n+4)=78`

Combine like terms, and we get:


`3n+6=78`

Subtract 6 from both sides.


`3n=72`

Divide both sides by 3, and we find our number to be:


`n=24`

Hope this helped! Good luck.