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.
\nTable 2: Temperature and ice-cream sold
\n| \n Temperature (oF) \n | \n\n 93 \n | \n\n 86 \n | \n\n 77 \n | \n\n 89 \n | \n\n 98 \n | \n\n 102 \n | \n\n 87 \n | \n\n 79 \n | \n
| \n Sales of Ice-cream (in kg) \n | \n\n 95 \n | \n\n 79 \n | \n\n 56 \n | \n\n 90 \n | \n\n 105 \n | \n\n 126 \n | \n\n 72 \n | \n\n 53 \n | \n
Calculate Sxx to 3 decimal places.
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\n", "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
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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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\nTable: Sales of history books with corresponding price
\n| \n x \n | \n\n Price (£) \n | \n\n 1.99 \n | \n\n 2.50 \n | \n\n 3.25 \n | \n\n 0.99 \n | \n\n 6.99 \n | \n\n 5.00 \n | \n\n 3.50 \n | \n\n 1.98 \n | \n
| \n y \n | \n\n Sales (in thousands) \n | \n\n 25 \n | \n\n 13 \n | \n\n 28 \n | \n\n 42 \n | \n\n 8 \n | \n\n 14 \n | \n\n 21 \n | \n\n 34 \n | \n
Give your answer to 2 decimal places when necessary.
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