Mr. Spears was purchasing supplies for his math classroom. He had 25 to spend. Mechanical pencils and erasers come in bundles of 10. Each eraser costs .50. Fill in the missing place in the equation to compute the cost of each mechanical pencil.

To compute the cost of each mechanical pencil, we need to subtract the cost of the erasers from the total amount that Mr. Spears had to spend.

The equation to compute the cost of each mechanical pencil is:

X + 0.50 = 25 - (10 * 0.50)

First, let's calculate the cost of the erasers: (10 * 0.50) = 5

Now, let's substitute the value into the equation:

X + 0.50 = 25 - 5

Simplifying further:

X + 0.50 = 20

Subtracting 0.50 from both sides of the equation:

X = 20 - 0.50

X = 19.50

Therefore, the cost of each mechanical pencil is $19.50.