A coach is assessing the correlation between the number of hours spent practicing and the average number of points scored in a game. The table below shows the data: Number of hours spent practicing
(x) 0 0.5 1 1.5 2 2.5 3 3.5 4
Score in the game
(y) 5 8 11 14 17 20 23 26 29

Part A: Is there any correlation between the number of hours spent practicing and the score in the game?Justify your answer. (4 points)

Part B: Write a function which best fits the data. (3 points)

Part C: What does the slope and y-intercept of the plot indicate? (3 points)

a)    

We have a perfect linear relationship between the two variables

b)    

Nowe we can find the means for x and y like this:  

And we can find the intercept using this:  

So the line would be given by:  

c) For this case the slope indicates that for each increase of the number of hours in 1 unit we have an expected increase in the score about 6 units.

And the intercept 5 represent the minimum score expected for any game

Step-by-step explanation:

We have the following data:

Number of hours spent practicing (x) 0 0.5 1 1.5 2 2.5 3 3.5 4

Score in the game (y) 5 8 11 14 17 20 23 26 29

Part a

The correlation coefficient is given:

For our case we have this:

n=9    

We have a perfect linear relationship between the two variables

Part b

Where:  

With these we can find the sums:  

And the slope would be:  

Nowe we can find the means for x and y like this:  

And we can find the intercept using this:  

So the line would be given by:  

Part c

For this case the slope indicates that for each increase of the number of hours in 1 unit we have an expected increase in the score about 6 units.

And the intercept 5 represent the minimum score expected for any game

Step-by-step explanation:

1) c 2143.6 cm

2) c 113.0 m

3) a 33.5 ft

4)   d 2 cm

5) c 20 mm

6) 180 in

7) d 120 ft

answer: c, the green line

step-by-step explanation:

there is no black line, eliminate b.

simple interest implies periodic payments, but the red line shows no payments, eliminate d.

simple interest has equal payments. if paid say every day, the graph is about a straight line (actually a stairstep).

the yellow line is not straight, eliminate a.

check: the green line is straight, answer is c.

simple interest with positive interest rate gives a straight line sloping up to the right. green line:

g(t) = $100 + ($200-$100) ÷ (20 years) × (t years)

= $100 + (4%/year) × ($100)(t years)

incidentally, the yellow line curving upward represents continuously compounded interest

y = $100 × 2^(t years / (14 assuming the yellow line hits $200 at 14 years. 2^0 is 1, so y(0) = $100; 2^(14/14) is 2, so y(14) = $200.