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The following table gives information on the amount of ice-cream sold (by weight) in a city centre café and the temperature (in degrees Fahrenheit) in the city. The data was collected on 8 random days.

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Table 2: Temperature and ice-cream sold

\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
\n

Temperature (oF)

\n
\n

93

\n
\n

86

\n
\n

77

\n
\n

89

\n
\n

98

\n
\n

102

\n
\n

87

\n
\n

79

\n
\n

Sales of Ice-cream (in kg)

\n
\n

95

\n
\n

79

\n
\n

56

\n
\n

90

\n
\n

105

\n
\n

126

\n
\n

72

\n
\n

53

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Calculate Sxx   to 3 decimal places.  

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Calculate Syy to 1 decimal place .

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Calculate Sxy to 1 decimal place.

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Calculate product moment correlation coefficient r to 3 decimal places.

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Identify the equation of regression line of ice-cream sales on temperature

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Ice-cream sales = 2.801 x temperature – 164.44

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", "

Ice-cream sales = 2.85 x temperature – 164.64

\n

 

", "

Ice-cream sales = 2.941 x temperature – 165.58

\n

 

", "

Ice-cream sales = 2.7801 x temperature – 166.44

\n

 

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Predict the ice-cream sales (in weight) when the temperature in the city reaches 102 o to 3 decimal places.

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