If there are 13 values in a data set in order from smallest to largest, what is the third quartile of the data set?

a. the mean of the 10th and 11th values
b. the mean of the 8th and 9th values
c. the mean of the 7th and 8th values
d. the mean of the 9th and 10th values

answer: 33 ( approx)

step-by-step explanation:

since, in the linear regression formula, the slope is the a in the equation y = b + ax ( by comparing it with the general equation of line y = mx + c )

where,

here given table is,

price ($), x   :           18         23       25       29       30       33

pairs sold, y :         16         13         10       8         6       2

so, ,   ,   ,

and   ,

thus, slop of the given line is,

⇒  

⇒   ≈ 33