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3 years ago

13

A baseball is dropped from a stadium seat that is 73 feet above the ground. Its height s in feet after t seconds is given by s(t

)=73−16t^2. Estimate how long it takes for the baseball to strike the ground.

1 answer:

lisov135 [29]3 years ago

8 0

0 = 73 - 16t^2
16t^2 = 73
4^2*t^2 = 73
(4t)^2 = 73
<span>sqrt(4t^2) = sqrt(73) </span>
4t = 8.5440
<span>t = 2.136</span>
ANSWER: 2.1 seconds

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3 years ago

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Answer:

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Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

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3 years ago

Read 2 more answers

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Answer: $15.3\pm0.198$

OR

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Step-by-step explanation:

The formula to find the confidence interval $(\mu)$ is given by :-

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, where n is the sample size

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$z_{\alpha/2}$ = Two tailed z-value for significance level of $\alpha$ .

Given : Confidence level = 95% = 0.95

Significance level = $\alpha=1-0.95=0.05$

$s= 1.6$

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thus , $\sigma=1.6$

By standard normal distribution table ,

Two tailed z-value for Significance level of 0.05 :

$z_{\alpha/2}=z_{0.025}=1.96$

Then, the 95% confidence interval for the mean credit hours taken by a student each quarter :-

$15.3\pm (1.96)\dfrac{1.6}{\sqrt{250}}\\\\ =15.3\pm 0.19833\\\\=\approx15.3\pm0.198\\\\=(15.3-0.198,\ 15.3+0.198)=(15.102,\ 15.498)$

Hence, the mean credit hours taken by a student each quarter using a 95% confidence interval. =(15.102, 15.498)

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3 years ago