List the numbers in order from smallest to largest:
1, 1 , 2, 3, 4, 6, 8, 9, 15
Median is the Middle value of the set = 4
Mode is the number that appears the most = 1
Mean is the average add the numbers together and divide by the quantity of numbers:
1 + 1 +2 + 3+ 4+ 6 +8 + 9+15 = 49 / 9 = 5.44
Range is the difference between the largest number and smallest number: 15 -1 = 14