9514 1404 393
Answer:
A) r = d/t
B) 221,760 ft/h
C) 42 mi/h
D) miles; the number is more comprehensible
Explanation:
A) Given d = rt
Divide by the coefficient of r to solve for r.
r = d/t
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B) Fill in the given numbers to find the rate in ft/h.
r = (665,280 ft)/(3 h) = 221.760 ft/h
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C) Multiply by the conversion factor (1 mi)/(5280 ft) to convert to miles.
(221,760 ft/h)(1 mi)/(5280 ft) = 42 mi/h
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D) For this scenario, miles per hour is a better unit for speed. Many people have seen that speed registered on a speedometer, so have some sense of what it means. Often numbers outside the range of 1 to 1000 are beyond ready comprehension.