lifetime pets\nwhich of the following is most likely true?\nthe mean and median are both in the interval 1…

lifetime pets\nwhich of the following is most likely true?\nthe mean and median are both in the interval 1 - 5.\nthe mean and median are both in the interval 6 - 10.\nthe mean is in the interval 6 - 10, and the median is in the interval 1 - 5.\nthe mean is in the interval 1 - 5, and the median is in the interval 6 - 10.
Answer
Explanation:
Step1: Calculate total number of adults
We have the frequencies for each interval: 1 - 5 has 14 adults, 6 - 10 has 9 adults, 11 - 15 has 6 adults and 16 - 20 has 2 adults. So the total number of adults $n=14 + 9+6 + 2=31$.
Step2: Find the median position
Since $n = 31$ (an odd - numbered data set), the median is the $\left(\frac{n + 1}{2}\right)$-th value. $\frac{31+1}{2}=16$-th value.
Step3: Determine the median interval
Counting the frequencies, the first 14 values are in the 1 - 5 interval. Since $14<16$ and $14 + 9=23>16$, the median is in the 6 - 10 interval.
Step4: Estimate the mean
To estimate the mean, we assume the mid - points of each interval: mid - point of 1 - 5 is 3, mid - point of 6 - 10 is 8, mid - point of 11 - 15 is 13 and mid - point of 16 - 20 is 18. The mean $\bar{x}=\frac{14\times3 + 9\times8+6\times13 + 2\times18}{31}=\frac{42+72 + 78+36}{31}=\frac{228}{31}\approx7.35$. So the mean is in the 6 - 10 interval.
Answer:
The mean and median are both in the interval 6 - 10.