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2 years ago

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The table shows the shipping costs for items of different values. A 2-column table with 4 rows. The first column is labeled tota

l cost of items (in dollars) with entries 25, 45, 50, 70. The second column is labeled shipping costs (in dollars) with entries 5.99, 8.99, 8.99, 10.99. Which best describes the strength of the model? a weak positive correlation a strong positive correlation a weak negative correlation a strong negative correlation

2 answers:

Lisa [10]2 years ago

4 0

A strong positive correlation.

Step-by-step explanation:

The question requires you to calculate the correlation coefficient and then make a conclusion about its value.

Form a table as shown where x is cost of items and y is shipping cost

x y xy x² y²

25 5.99 149.8 625 35.9

45 8.99 404.6 2025 80.8

50 8.99 449.5 2500 80.8

70 10.99 769.3 4900 120.8

190 34.96 1773.2 10050 318.3 ------sum

The formula for correlation coefficient follows;

r=n(∑xy)-(∑x)(∑y) ÷ √{[n∑x²-(x)²] [n∑y²-(y)²]}

where n=4

r=4(1773.2)-(190)(34.96) ÷ √{[4(10050)-190²] [4(318.3)-34.96²]}

r=450÷ √{4100*51)

r=450÷√209100

r=450÷457.3

r=0.98409

The value of r indicates a stronger positive correlation

Learn More

Correlation coefficient :brainly.com/question/12528676

Keywords :shipping costs,cost of items, strength of the model

#LearnwithBrainly

krok68 [10]2 years ago

3 0

Answer:

B

Step-by-step explanation:

a strong positive correlation

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