after teaching a science unit on sound waves, mr. conway gave his students a quiz, and he recorded each…

Explanation:

Step1: Count the data - points

Count the number of 'X's. There are 1 + 1+ 1+ 2+ 3+ 7+ 4 = 19 data - points.

Step2: Find the median

Since (n = 19) (an odd number), the median is the (\left(\frac{n + 1}{2}\right))-th value. (\frac{19+1}{2}=10) - th value. Counting the 'X's from left to right, the 10 - th value is 8.

Step3: Calculate the mean

The sum of the data: (2\times1+6\times1 + 7\times2+8\times3+9\times7+10\times4=2 + 6+14 + 24+63+40 = 149). The mean (\bar{x}=\frac{149}{19}\approx7.84\approx8).

Step4: Analyze the effect of the outlier

The outlier is 2 (it is far from the other data - points). If we remove the outlier, the sum becomes (149 - 2=147) and the number of data - points becomes (19 - 1 = 18). The new mean is (\frac{147}{18}\approx8.17\approx8). The median of the 18 data - points (an even number) is the average of the 9 - th and 10 - th ordered values. After re - ordering without 2, the median is still 8. So the mean would change.

Answer:

8 ... 8 ... mean