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OpenStax, Elementary Algebra 2e §1.9 Properties of Real Numbers · Exercise 95 · Algebra · Expressions

Properties of Real Numbers · Exercise 95

Insurance copayment Carrie had to have 5 fillings done. Each filling cost $80. Her dental insurance required her to pay 20% of the cost as a copay. Calculate Carrie’s copay:

ⓐ First, by multiplying 0.20 by 80 to find her copay for each filling and then multiplying your answer by 5 to find her total copay for 5 fillings.
ⓑ Next, by multiplying [5(0.20)](80)
ⓒ Which of the properties of real numbers says that your answers to parts (a), where you multiplied 5[(0.20)(80)] and (b), where you multiplied [5(0.20)](80), should be equal?

This is an open-ended exercise: its source gives no single answer.

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OpenStax, Elementary Algebra 2e · §1.9 Properties of Real Numbers · Exercise 95

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