Starting with the data values 70 and 100, add three data values to the sample so that the mean is 90, the median is 91, and the mode is 91. Please show all of your work.
Since the mode is the most frequently observed score, at least two scores need to be 91.
Mean = sum of scores/number of scores.
90 = (70+91+91+100+x)/5
Solve for x for the fifth value.