Recall which type of error can be reduced by taking an average of multiple measurements.

The type of error that can be reduced by taking an average of multiple measurements is called random error.

Here are the steps to understand why:

1. Random errors are statistical fluctuations (in either direction) in the measured data due to the precision limitations of the measurement device. They can occur for a variety of reasons such as environmental changes during the experiment or the way the observer uses the measuring instrument.

2. When you take multiple measurements, you are likely to get slightly different results each time due to these random errors.

3. By taking an average of these measurements, you can reduce the impact of these random fluctuations. This is because some errors will be overestimates, some will be underestimates, and they can often cancel each other out to some extent.

4. Therefore, the average of multiple measurements is likely to be closer to the true value than any single measurement, reducing the overall random error.

5. It's important to note that this process reduces only random error. Systematic errors, which are consistent inaccuracies in measurement, cannot be reduced by taking multiple measurements.