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3 years ago

Please help with this exercise..

Mathematics

1 answer:

valkas [14]3 years ago

4 0

Answer:

a. 1.0453 minutes/ft²

b. 120 minutes (2 hours)

c. $50

Step-by-step explanation:

a. The area is (10.5 ft)×(12.3 ft) = 129.15 ft². Then the time per square foot is ...

... (2.25 hours)/(129.15 ft²) ≈ 0.0174216 hours/ft² ≈ 1.0452396 min/ft²

b. Multiplying the number of square feet by the time per square foot gives the time for the smaller area:

... (1.0452396 min/ft²) × (114.8 ft²) = 120 min = 2 hours

c. The charge is assumed to be proportional to the time, so the charge for the smaller time is ...

... (2 hours)/(2.25 hours) × $56.25 = (8/9)×$56.25 = $50.00

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