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Aleksandr [31]
2 years ago
6

A cyclist is riding from the city to the country. She rides 20 miles each hour. At the beginning of the 1 st hour, she is 10 mil

es away from the city center. At the beginning of the 2nd hour, she is 30 miles away from the city center. Write an explicit formula to show her distance from the city at any given hour. Then use the formula to find her distance at the beginning of the 5th hour. ​
Mathematics
1 answer:
strojnjashka [21]2 years ago
7 0

Answer:

450miles

Step-by-step explanation:

Because she is riding at 20 miles per houre means that she ride 450 miles in 5 houre.

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Step-by-step explanation:

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The equation of a line has the following format:

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3 years ago
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a) E(\hat \theta_1) =\frac{1}{2} [E(X_1) +E(X_2)]= \frac{1}{2} [\mu + \mu] = \mu

So then we conclude that \hat \theta_1 is an unbiased estimator of \mu

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Step-by-step explanation:

For this case we know that we have two random variables:

X_1 , X_2 both with mean \mu = \mu and variance \sigma^2

And we define the following estimators:

\hat \theta_1 = \frac{X_1 + X_2}{2}

\hat \theta_2 = \frac{X_1 + 3X_2}{4}

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In order to see if both estimators are unbiased we need to proof if the expected value of the estimators are equal to the real value of the parameter:

E(\hat \theta_i) = \mu , i = 1,2

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E(\hat \theta_1) = E(\frac{X_1 +X_2}{2})

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E(\hat \theta_1) =\frac{1}{2} [E(X_1) +E(X_2)]= \frac{1}{2} [\mu + \mu] = \mu

So then we conclude that \hat \theta_1 is an unbiased estimator of \mu

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