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4 years ago

SOMEONE WHO CAN SIMPLY ORDER INTERVALS!

Mathematics

1 answer:

OlgaM077 [116]4 years ago

3 0

Answer:

2.5 seconds.

Step-by-step explanation:

Find the value of t when the height is 28 feet:

-16t^2 + 56t + 4 = 28

-16t^2 + 56t - 24 = 0

-8(2t^2 - 7t + 3) = 0

-8(2t - 1)(t - 3) = 0

t = 0.5, 3 seconds.

So on the upward journey the rock is at 28 feet at 0.5 second after the throw and at 3 seconds it is at 28 feet again while it is falling back.

Therefore the period when it is at least 28 feet above the ground is 3.0 - 0.5 = 2.5 seconds.

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Answer:

Q.1: A

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3 years ago

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Over the past several years, the proportion of one-person households has been increasing. The Census Bureau would like to test t

bixtya [17]

Answer:

For this case we can find the critical value with the significance level $\alpha=0.05$ and if we find in the right tail of the z distribution we got:

$z_{\alpha}= 1.64$

The statistic is given by:

$z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}$ (1)

Replacing we got:

$z=\frac{0.344 -0.27}{\sqrt{\frac{0.27(1-0.27)}{125}}}=1.86$

Since the calculated value is higher than the critical value we have enough evidence to reject the null hypothesis and we can conclude that the true proportion of households with one person is significantly higher than 0.27

Step-by-step explanation:

We have the following dataset given:

$X= 43$ represent the households consisted of one person

$n= 125$ represent the sample size

$\hat p= \frac{43}{125}= 0.344$ estimated proportion of households consisted of one person

We want to test the following hypothesis:

Null hypothesis: $p \leq 0.27$

Alternative hypothesis: $p>0.27$

And for this case we can find the critical value with the significance level $\alpha=0.05$ and if we find in the right tail of the z distribution we got:

$z_{\alpha}= 1.64$

The statistic is given by:

$z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}$ (1)

Replacing we got:

$z=\frac{0.344 -0.27}{\sqrt{\frac{0.27(1-0.27)}{125}}}=1.86$

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3 years ago

Rewrite the expression c + 0.25c using fractions instead of decimal numbers.

gogolik [260]

Answer:

$\huge\boxed{\frac{5c}{4},\ or\ c+\frac{1}{4}c,\ or\ c+\frac{c}{4}}$

Step-by-step explanation:

The decimal 0.25 can simply be converted into a fraction by putting it over 100.

0.25 = $\frac{25}{100}$

Then, simply divide both the numerator and denominator by 25 to get

$\frac{25/25}{100/25}$ , or $\frac{1}{4}$

Hope it helps :)

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3 years ago

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yarga [219]

Answer:

102

Step-by-step explanation:

Each triangle will have a perimeter of 3. When joined, the outside triangles will have 2 sides showing, or 2 inches. The middle 98 will only have one free side, or one inch. This means that 98*1 + 2*2 = 102

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3 years ago

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Answer: I believe it would be 15.42

Step-by-step explanation:

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4 years ago

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*SOMEONE WHO CAN SIMPLY ORDER INTERVALS!*

SOMEONE WHO CAN SIMPLY ORDER INTERVALS!