Math 111 Applied College Algebra

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Math 111 Applied College Algebra

• Problem of the Day

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Day 3 Increasing Harvest by Fertilizing the
Crops

• From College Algebra Concepts through
  Functions, by Sullivan Sullivan, p.162
• The concept If you fertilize your fields, your
  harvest (yield) will increase
• But
• If you fertilize too much, youll effectively
  poison your crops and your harvest will decrease.

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Day 3 contd

• A farmer collected the data given in the table to
  the right, which shows crop yields Y for various
  amounts x of fertilizer used.

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Day 3 Fertilizing Crops - contd

• Draw a scatter diagram of the data. What is the
  dependent variable and what is the independent
  variable?
• Describe what happens as the amount of fertilizer
  used increases. Is this what you expect?
  Explain.

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Day 3 Fertilizing Crops - contd

• Use your graphing calculator to determine the
  parabola of best fit. That is, determine the
  quadratic regression for this data, and graph it
  over your scatterplot.
• Use the function found above to determine the
  optimal amount of fertilizer to apply.
• Use the function to predict crop yield when the
  optimal amount of fertilizer is applied.