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2 years ago

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Mathematics

1 answer:

kow [346]2 years ago

3 0

$1)\\\\\dfrac{-45}{-5}=45:5=9$

$2)\\(-2)(4)=-8\\(2)(-4)+-8\\-16:2=-8\\-16:(-2)=8\neq-8\\\\\text{All of the following expressions have the same value except}\ -16:-2.$

$3)\\-3^2=-3\cdot3=-9$

$(-2)^4=(-2)(-2)(-2)(-2)=16\\-2^4=-(2)(2)(2)(2)=-16\neq16\\(-2)(-2)(-2)(-2)=16\\2^4=(2)(2)(2)(2)=16\\\\\text{All of the following are equivalent except}\ -2^4.$

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Answer:

(a) The 90% confidence interval is: (0.60, 0.63) Correct interpretation is (3).

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Step-by-step explanation:

(a)

Let X = number of dog owners who take more pictures of their dog than of their significant others or friends.

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The (1 - α)% confidence interval for population proportion is:

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The critical value of z for a 90% confidence level is:

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Construct a 90% confidence interval for the population proportion of dog owners who take more pictures of their dog than their significant others or friends as follows:

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Thus, the 90% confidence interval for the population proportion of dog owners who take more pictures of their dog than their significant others or friends is (0.60, 0.63).

Interpretation:

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Correct option is (3).

(b)

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The sample proportion is:

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The critical value of z for a 95% confidence level is:

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Construct a 95% confidence interval for the population proportion of dog owners who are more likely to complain to their dog than to a friend as follows:

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The confidence level
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Because of this the critical value of z in part (b) is more than that in part (a).

Also the margin of error in part (b) is 0.016 which is more than the margin of error in part (a), 0.015.

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