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listed below are the overhead widths (in cm) of seals measured from pho…

Question

listed below are the overhead widths (in cm) of seals measured from photographs and the weights (in kg) of the seals. construct a scatterplot, find the value of the linear correlation coefficient r, and find the critical values of r using \\( \alpha = 0.01 \\). is there sufficient evidence to conclude that there is a linear correlation between overhead widths of seals from photographs and the weights of the seals?

\\( \

$$\begin{array} { c | c c c c c c } { \\text { overhead width } } & { 7.1 } & { 7.6 } & { 9.8 } & { 9.4 } & { 8.9 } & { 8.3 } \\\\ \\hline \\text { weight } & { 113 } & { 188 } & { 249 } & { 201 } & { 206 } & { 190 } \\end{array}$$

\\)

click here to view a table of critical values for the correlation coefficient.

construct a scatterplot. choose the correct graph below.

the linear correlation coefficient is \\( r = \\) (round to three decimal places as needed.)

Explanation:

Step1: Define variables

Let \( x = \text{Overhead Width} \), \( y = \text{Weight} \), \( n = 6 \).

Step2: Calculate sums

\( \sum x = 7.1 + 7.6 + 9.8 + 9.4 + 8.9 + 8.3 = 51.1 \)
\( \sum y = 113 + 188 + 249 + 201 + 206 + 190 = 1147 \)
\( \sum xy = (7.1×113)+(7.6×188)+(9.8×249)+(9.4×201)+(8.9×206)+(8.3×190) = 792.3 + 1428.8 + 2440.2 + 1889.4 + 1833.4 + 1577 = 9961.1 \)
\( \sum x^2 = 7.1^2 + 7.6^2 + 9.8^2 + 9.4^2 + 8.9^2 + 8.3^2 = 50.41 + 57.76 + 96.04 + 88.36 + 79.21 + 68.89 = 440.67 \)
\( \sum y^2 = 113^2 + 188^2 + 249^2 + 201^2 + 206^2 + 190^2 = 12769 + 35344 + 62001 + 40401 + 42436 + 36100 = 229051 \)

Step3: Compute r formula numerator

\( n\sum xy - (\sum x)(\sum y) = 6×9961.1 - 51.1×1147 = 59766.6 - 58611.7 = 1154.9 \)

Step4: Compute r formula denominator

\( \sqrt{[n\sum x^2 - (\sum x)^2][n\sum y^2 - (\sum y)^2]} = \sqrt{[6×440.67 - 51.1^2][6×229051 - 1147^2]} = \sqrt{[2644.02 - 2611.21][1374306 - 1315609]} = \sqrt{32.81×58697} ≈ \sqrt{1925858.57} ≈ 1387.75 \)

Step5: Calculate r

\( r = \frac{1154.9}{1387.75} ≈ 0.832 \)

Step6: Find critical values

For \( n=6 \), \( α=0.01 \), critical values \( ±0.917 \).

Step7: Compare r and critical values

\( |0.832| < 0.917 \), so no sufficient evidence.

Answer:

Scatterplot: (Assuming B matches the positive trend; exact graph not visible, but r calculation is 0.832)
Linear correlation coefficient: 0.832
Critical values: ±0.917
Sufficient evidence? No

(Note: Scatterplot choice depends on visual match, but numerical results are as above.)