What is the ratio of a grid constructed with lead strips that are 72 units tall and separated by radiolucent material 6 units wide?

To determine the ratio of a grid constructed with lead strips and radiolucent material, you can use the formula for grid ratio:

Grid ratio = Height of lead strips / Width of interspace

In this case, the height of the lead strips is 72 units, and the width of the radiolucent material is 6 units. Applying the formula:

Grid ratio = 72 units (height) / 6 units (width) = 12

This calculation shows that the ratio of the grid is 12:1. A grid ratio of 12:1 indicates that for every 12 units in height of the lead strips, there are 1 unit of width in the interspace. This is significant in radiologic technology because a higher grid ratio often results in better scatter radiation absorption, improving image quality.

The other options represent different grid ratios that would apply if the dimensions were different. However, based on the provided dimensions, the correct and precise determination leads to a ratio of 12:1.