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Pachacha [2.7K]
3 years ago
15

For the last 4.5 hours, the temperature has decreased at a rate of 2.8 Degrees Fahrenheit per hour. Which best represents the ov

erall change in temperature over this time period? –12.6 Degrees Fahrenheit –1.6 Degrees Fahrenheit 1.6 Degrees Fahrenheit 12.6 Degrees Fahrenheit?
Please help me!
Mathematics
2 answers:
faust18 [17]3 years ago
7 0

Answer:

The overall change in temperature over the time period ∆T = -12.6°F

Step-by-step explanation:

Rate of change of temperature r = -2.8°F per hour

Time t = 4.5 hours

The overall change in temperature ∆T = Rate of change of temperature × time period

∆T = r × t

∆T = -2.8°F per hour × 4.5 hours

∆T = -12.6°F

The overall change in temperature over the time period is -12.6°F

Step-by-step explanation:

Mars2501 [29]3 years ago
4 0

Answer:

-12.6°F

Step-by-step explanation:

that's the answer

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A. 10 cm

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Customers arrive at a movie theater at the advertised movie time only to find that they have to sit through several previews and
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Answer:

Using a 90% confidence level

A. A sample size of 68 should be used.

B. A sample size of 98 should be used.

Step-by-step explanation:

I think there was a small typing mistake and the confidence level was left out. I will use a 90% confidence level.

We have that to find our \alpha level, that is the subtraction of 1 by the confidence interval divided by 2. So:

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72 seconds is 72/60 = 1.2 minutes.

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1.2\sqrt{n} = 6*1.645

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B. If we want to estimate the population mean time for previews at movie theaters with a margin of error of 1 minute, what sample size should be used?

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