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Margaret [11]
2 years ago
15

In order to fairly set flat rates for auto mechanics, a shop foreman needs to estimate the average time it takes to replace a fu

el pump in a car. How large a sample must he select if he wants to be 90% confident that the average time is within 20 minutes of the sample average? Assume the standard deviation of all times is 40 minutes.
Mathematics
1 answer:
Ede4ka [16]2 years ago
4 0

Answer:

ME = 1.96(45)/sqrt(n) 25 = 1.96(45)/sqrt(n) n = (1.96(45)/25)^2 = 6

Step-by-step explanation:

yw

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find the exponential regression equation for the data points (-4, 0.75), (-2, 6), (3, 28), and (5, 162)
zubka84 [21]
<span>for that, what you need is a calculator... like say a TI(texas instruments) 83 or 83plus or higher, will do regressions, if you have an android device like a phone or tablet, you can also get an app from the play store "Andie's graph", is a TI calculator emulator, it works just like the calculator itself, you'd only need the ROM 

</span><span>that said, you can also use some online calculators for that.
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<span>I could give you a direct link to one, but this site has issues with links, if you do a quick search in google for "keisan exponential regression calculator", it should be the first link, is from the Casio site.
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<span>you could do regressions in a spreadsheet as well.... you could check online for an "addin" or "extension", if you use MS Excel, pretty sure there are some addins for regressions.
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if I recall correctly, Excel does regressions natively, but the addins are just frontends, is all, just some added interfacing.

anyhow, if you have an Android device Andie Graph works peachy, I have an 83plus, 84, 86 in it, they all work just like my old TI83plus.

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8 0
3 years ago
An officer printer prints 25 photos in 12.5 minutes. A home printer prints 15 photos in 6 minutes. Which printer is faster, How
ollegr [7]

Answer:

The home printer is faster.

Step-by-step explanation:

25 photos in 12.5 minutes

12.5 is half of 25 and therefore this is a two to one ratio.

So 2 photos print in 1 minute with the office printer.

And 4 photos in 2 minutes(this is relevant later)

The home printer prints 15 photos in 6 minutes. Since 15 is not divisible by 6 without a remainder divide both by 3.

So 5 photos in 2 minutes. This is faster than the office printer.

To find how many photos it would print in 12 more minutes, simply multiply 15 by two, since the minutes(6) was multiplied by 2 to get 12. This leaves you with an answer of 30 photos in 12 minutes

7 0
2 years ago
Read 2 more answers
Scrieți multipli lui 7 mai mari decât 10 și mai mici decât 20​
beks73 [17]
<h2>Helloooo!!! Marie Here!!!</h2><h2 />

The answer is here:

  • 7 . 2 = 14, 10 >14 > 50

  • 7 . 3 = 21, 10 > 21 > 50

  • 7 . 4 = 28, 10 > 28 > 50

  • 7 . 5 = 35, 10 > 35 > 50

  • 7 . 6 = 42, 10 > 42 > 50

<h3>Hope This Helps! Have A GREAT Day!</h3>

3 0
3 years ago
What is 2/3 x 21 and 15 x 2/3 and witch is greater
ANTONII [103]
2/3 x 21 is correct because 21 is bigger than 15

6 0
3 years ago
Read 2 more answers
Jacy earns 14$ each second. He earns 14$ each second for 18 years. How much money would he have if he saved up the money?
Ratling [72]

they deleted my answer and they wont tell me why- let me try again

<u><em>answer:</em></u> jacy would earn a total of $7,952,345,352 if he saved up for a total of 18 years.

<u><em>explanation:</em></u>

the total of seconds among 18 years: <em>568,024,668 seconds.</em>

we now take the 568,024,668 and multiply it by 14.

<em>our final answer is </em><em>$7,952,345,352.</em>

i dont know if this is a genuine question or not but here-

7 0
2 years ago
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