Answer:
Mode: 13
Mean: 16
Range: 7
Median: 15.5
Step-by-step explanation:
Mode, the number that occurred most often in the set of data was 13
Mean, 13+13+18+20= 64/(the amount of numbers in the set of data)4 = 16
Range, the smallest number in the set subtracted from the largest (20-13=7)