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1 year ago

Dont go on bit. ly/3a8Nt8n (virus warning)

Mathematics

2 answers:

vlada-n [284]1 year ago

8 0

Okay! thank you so much for the awarness!

Rzqust [24]1 year ago

8 0

Thank you but can u Please help — Neil is going to a bookstore 45 miles away. The bridge was closed on the way back, so
he had to take an alternate route and had to drive 15 mph slower, which make the trip
back take 7 minutes longer. How fast was he going on the way to the bookstore?

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Catherine has $54. She plans to spend more than $20 of the money for a painting canvas. The rest will go toward paints. Each tub

kakasveta [241]

Answer:

4. 54- 8.5x>20

Step-by-step explanation:

Catherine only has $54, so she cannot spend more than that.

The canvas will cost at least $20, but we don't know how much exactly.

The tubes cost $8.50 each.

So, she starts with a total budget of $54, out of which she will buy paints (8.5x) and she wants to have at least $20 left for canvas.

So, we transpose those facts into the inequity:

54 - 8.5x > 20

8 0

1 year ago

Read 2 more answers

Steve stayed after school for extra activities 55% of the 180 school days this year. How many days did Steve stay after school?

musickatia [10]

Answer:

11/20 or 99/180 days

Step-by-step explanation:

55/100 converted to ?/180

180/100=1.8

so you would do the same on the numerator which is 55*1.8=99

99/180= 33/60=11/20

7 0

1 year ago

Explain how to write and evaluate an algebraic expression that represents the situation. The blueberries were divided equally in

ser-zykov [4K]

The variable is the number of blueberries, the operation is division, and the constant is 6. Write the division expression as the fraction, b/6 . To evaluate, substitute 210 in for the variable, b, and simplify. 210 divided by 6 is 35. So each bowl has 35 blueberries.

4 0

1 year ago

Read 2 more answers

Aisha runs a tutoring business.with plan 1 students may choose to pay $15 per hour

Elza [17]

What is the question u are asking?

4 0

1 year ago

After the 2008 elections, it is desired to estimate the proportion of Florida voters who now regret that they did not vote.

Sonja [21]

Answer:

$n=\frac{0.5(1-0.5)}{(\frac{0.02}{1.64})^2}=1681$

And rounded we got 1681

Step-by-step explanation:

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".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

$p$ represent the real population proportion of interest

$\hat p$ represent the estimated proportion for the sample

n is the sample size required (variable of interest)

$z$ represent the critical value for the margin of error

Solution to the problem

The population proportion have the following distribution

$p \sim N(p,\sqrt{\frac{\hat p(1-\hat p)}{n}})$

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 90% of confidence, our significance level would be given by $\alpha=1-0.90=0.10$ and $\alpha/2 =0.05$ . And the critical value would be given by:

$z_{\alpha/2}=-1.64, z_{1-\alpha/2}=1.64$

The margin of error for the proportion interval is given by this formula:

$ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}$ (a)

And on this case we have that $ME =\pm 0.02$ and we are interested in order to find the value of n, if we solve n from equation (a) we got:

$n=\frac{\hat p (1-\hat p)}{(\frac{ME}{z})^2}$ (b)

We can assume that the estimates proportion is 0.5 since we don't have other info provided to assume a different value. And replacing into equation (b) the values from part a we got:

$n=\frac{0.5(1-0.5)}{(\frac{0.02}{1.64})^2}=1681$

And rounded we got 1681

8 0

2 years ago