Theory
A frequency tells you how many times a value appears. In a frequency table, each row stands for repeated values.
For the mean, multiply each value by its frequency. Add these products, then divide by the total frequency.
For the median, use the total frequency to find the middle position. Then use cumulative frequency to locate that position in the table.
For the mode, choose the value with the highest frequency.
For the range, use the largest value with a frequency and subtract the smallest value with a frequency.
If students are unsure, expanding the table into a list can help for small frequencies, but it is too slow for larger exam questions.