Determine the percent yield of MgO for your experiment for each trial(Picture of question included)ive had help on this but im still struggling on the concept

To calculate the percentage of yield we use the following formula:
percent yield = (Actual Yield/Theoretical Yield) x 100%
For trial 1:
actual yield: 0.509
theoretical yield: 0.52
percent yield: (0.509/0.52) x 100%
percent yield: 97.9%
For trial 2:
actual yield: 0.672
theoretical yield: 0.69667
percent yield: (0.672/0..69667) x 100%
percent yield: 96.5%
Answer: Trial 1: 97.9%
Trial 2: 96.5%