Answer:
median = 11.5 . first quartile = 9.5 , third quartile = 14.5
Explanation:
arrange the 12 numbers in order:
9,9,9,10,11,11,12,13,14,15,16,17
median
since there is an even number (12)
we can divide by 2
12 /2
= 6th position and 7th position
= 11 + 12
= 23 / 2 = 11.5
median is 11.5
first quartile
is also known as the lower quartile is half of the median position
6/2 = 3rd position and 7/2 = 3.5th position
9 + 10 = 19
19 / 2 = 9.5
first quartile is 9.5
third quartile
also known as upper quartile
is the position of median + position of lower quartile
= 6 +3 = 9th position and 7 +3 = 10th position
= 14 + 15 = 29
29/2 = 14.5
third quartile is 14.5