The best estimate for this correlation would be B) 0.9.
We can see that the number is constantly going up, which would throw out the D answer.
We can also see that for every time the x goes up 1, the y goes up a little less than one. We can see that in the ordered pairs that exist on the graph such as (3, 2), (8, 6) and (2.1, 1.9).
Since the y values are just lower than the x, the correlation would be just under one. Therefore, 0.9 is an accurate estimation.
The summation symbol means we use the variable i in the equation from the given range. In this case, we are given with the equation 3 i - 15 and i ranges from 2 to 7. The summation using simply the calculator is equal to -9. The answer to this problem is -9.
Answer:
Step-by-step explanation:
n could be : -14, -13, -12... -1, 0 , 1, 2, 3 ,4,5
We can compare by converting Johnny's reading time into the same unit of Jacky's, hours.
There are 60 minutes in an hour, so use this:

15 < 20, so Johnny read faster. This is 5 pages faster per hour than Jacky.