First, we need to simplify the equation by combining like terms.

2z + 4 + 1/2z - 1 + 4/5 - z = 25

First, let's combine the z terms:

2z + 1/2z - z = z/2

Next, let's combine the constant terms:

4 - 1 + 4/5 = 4 + 4/5 - 1 = 20/5 + 4/5 - 5/5 = 24/5

Now, our equation becomes:

z/2 + 24/5 = 25

Next, we need to get rid of the fractions by finding a common denominator:

z/2 = 25 - 24/5

z/2 = 125/5 - 24/5

z/2 = 101/5

Now, to solve for z, we multiply by 2 on both sides:

z = 2 * 101/5

z = 202/5

Therefore, the solution to the equation is z = 202/5.