Using a scale that has increments that are somewhat large, you could get an error if you reach half of the measuring unit. This is because when you arrive at a measurement greater than half of the measuring unit, you would have to round it up. Therefore, the greatest possible error when measuring to the nearest quarter of an inch is 1/8 inch. The greatest possible error when measuring to the nearest quarter of an inch is how the reader reads the measurement. Sometimes, we base our answers to what we can see and what we see may be different from others.