Mean is calculated by adding all numbers and dividing by how many there are. I have set up an equation to find x from the given mean.

To cancel out the denominator, multiply both sides by 4.

When that is done, you are left with:

Combine like terms:

Add 5 to both sides, cancelling out the -5 on the left.

Your answer is 51.
If you want to check your work, plug in 51 for x.

