Question

the water company has a different monthly pricing plan for residential customers than for business customers. for each pricing plan, cost (in dollars) depends on water used (in hundreds of cubic feet, hcf), as shown below.

(a) if the monthly water usage is 22 hcf, which plan costs less?

• residential plan
• business plan

how much less does it cost than the other plan?
$4

(b) for what amount of monthly water usage do the plans cost the same?

if the monthly water usage is less than this amount, which plan costs more?

• residential plan
• business plan

Explanation:

Analyze part (a) at usage of 22 HCF

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Find intersection point for part (b)

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Compare costs below intersection point

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Answer:

Question 1

(a) If the monthly water usage is 22 HCF, which plan costs less?

• Business Plan

How much less does it cost than the other plan?

• \$6

Question 2

(b) For what amount of monthly water usage do the plans cost the same?

• 14 HCF

If the monthly water usage is less than this amount, which plan costs more?

• Business Plan