A manufacturer claims that the mean lifetime,u , of its light bulbs is 51 months. The standard deviation of these lifetimes is 7 months. Sixty bulbs are selected at random, and their mean lifetime is found to be 53 months. Can we conclude, at the 0.1 level of significance, that the mean lifetime of light bulbs made by this manufacturer differs from 51 months?
Perform a two-tailed test. Then fill in the table below.
Carry your intermediate computations to at least three decimal places, and round your responses as specified in the table. (If necessary, consult a list of formulas.)
the null hypothesis:
The alternative hypotehsis:
The type of test statistic (choose Z, t, Chi-square, or F)
The value of the test statistic (round to at least three decimal places:
Can we conclude that the mean lifetime of the bulbs made by this manufacture differ from 51 months?

Answers

Answer 1

Answer:

We reject  H₀, and conclude thet the mean lifetime of the bulbs differ from 51 month

Step-by-step explanation:

Manufacturing process under control must produce items that follow a normal distribution.

Manufacturer information:

μ  =  51 months     mean lifetime

σ  =  7 months       standard deviation

Sample Information:

x  =  51 months

n  =  60

Confidence Interval  =  90 %

Then significance level  α  =  10 %  α  =  0.1    α/2  =  0,05

Since it is a manufacturing process the distribution is a normal distribution, and with   n = 60 we should use a Z test on two tails.

Then from z- table z(c) for  α = 0,05  is  z(c)  = 1.64

Hypothesis  Test:

Null Hypothesis                              H₀            x  =  μ

Alternative Hypothesis                  Hₐ            x ≠  μ

To calculate z statistics  z(s)

z(s)  =   (  x   -  μ )  / σ /√n

z(s)  =   (  53  -  51 ) / 7 /√60

z(s)  =  2 * 7.746 / 7

z(s)  = 2.213

Comparing  z(s)  and  z(c)

z(s)  >  z(c)   then  z(s)  is in the rejection region

We reject  H₀, and conclude thet the mean lifetime of the bulbs differ from 51 month


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Because the chords are the same length they need to be equal distance from the center of the circle

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I will give BRAINLIEST to whoever answers correctly first!!!

Sophie wants to buy a pair of scissors that cost $1.82. If she gives the cashier a five dollar bill, how
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Answers

$3.18

Explanation: I am a cashier hahaha

Answer:

Sophie will get $3.18 back in change.

Step-by-step explanation:

You do 5.00-1.82 and you get 3.18, which is equal to the change that Sophie will get.

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Answer:

125

Step-by-step explanation:

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9.09(m2)??
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in rectangle ABCD above,
1. How many opposite sides are equal?
2. Name the parallel opposite sides.
3. Name the opposite angles that are equal.
4. How many right angles can you identify?
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6. How many triangles can you identify?
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true or false?
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Answers

Answer and Step-by-step explanation:

1. 2 pairs (aka 4 sides) of Opposite Sides are equal

2. AB and DC are parallel, and AD and BC are parallel  

3. Angles BDC and ACD are equal, angles DAC and DBC are equal, the angles ADB and BCD are equal, angles CAB and DBA are equal

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#teamtrees #PAW (Plant And Water)

expand 3e(e+4)
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Answers

Answer:

[tex]3e^{2} + 12e[/tex]

Step-by-step explanation:

[tex]3ee+3e4[/tex]

[tex]3ee+3 * 4e[/tex]

[tex]3e^{2} + 12e\\[/tex]

[tex]3 \: {e}^{2} + 12 \: e[/tex] ✅

[tex]\large\mathfrak{{\pmb{\underline{\red{Step-by-step\:explanation}}{\orange{:}}}}}[/tex]

[tex]3 \: e \: ( \: e + 4 \: ) \\ \\ = 3 \: e \times \: e + 3 \: e \times 4 \\ \\ = 3 \: {e}^{2} + 12 \: e[/tex]

[tex]\large\mathfrak{{\pmb{\underline{\orange{Mystique }}{\orange{♡}}}}}[/tex]

please help picture included
Match the verbal expression (term) with its algebraic expression (definition). Match Term Definition Some number A) a = 2 increased by two A variable decreased B) b + 2 by two Product of an C) y2 unknown value and two D) X - 2 Quotient of some number and two An unknown value E) 22 squared​

Answers

9514 1404 393

Answer:

  B, D, E, A, C

Step-by-step explanation:

The main idea here is to use your English comprehension skill to determine the meaning of the phrase, then use your math understanding to write it in symbols. Turning off your brain at the sight of a "word problem" will not be productive.

The wording "some number" or "a variable" or "unknown value" all refer to a variable, typically represented by a single letter. Letters commonly use are {a, b, c, x, y, z}, but variables are not restricted to that set (nor to single letters, nor lower case letters).

In most cases, the math expression is a direct translation of the English expression using the usual math symbols. Values are generally increased by addition, decreased by subtraction, squared using an exponent of 2. A product is the result of multiplication, and a quotient is the result of division.

Top-to-bottom, the boxes on the left will be filled with B, D, E, A, C.

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Step-by-step explanation:

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Answer:

a = 2

Step-by-step explanation:

Use Pythagorean Theorem:

[tex]a^2+b^2=c^2\\a^2+2.1^2=2.9^2\\a^2+4.41=8.41\\a^2=4\\\sqrt{a^2}=\sqrt{4}\\a=2[/tex]

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Answers

9514 1404 393

Answer:

  x = 5

Step-by-step explanation:

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A + B + C = 4
step by step please​

Answers

Step-by-step explanation:

Let's solve for a.

a+b+c=4

Step 1: Add -b to both sides.

a+b+c+−b=4+−b

a+c=−b+4

Step 2: Add -c to both sides.

a+c+−c=−b+4+−c

a=−b−c+4

Answer:

a=−b−c+4

(hope this helped plz mark brilliant)

PLEASE HELP ME FAST I WILL GIVE BRAINLYEST

Answers

7.)

cbrt(1200)

10.63

8.)

sqrt(112)

10.58

Answer:

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Step-by-step explanation:

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Answers

Answer:

a= 250

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Step-by-step explanation:

There's many solutions but this was the first one I could come up with.

Answer:

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Step-by-step explanation:

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Answer:

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Step-by-step explanation:

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Answer:

B. BC

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Sadie and Connor both play soccer. Connor scored 2 times as many goals as Sadie. Together they scored 9 goals. Could Sadie have scored 4 goals? Why or why not?

Answers

Answer:

no

the goal total would be too high

Step-by-step explanation: If Sadie had scored 4 goals, Connor would have scored 2 times 4 = 8 goals. Their goal total would then be 4+8 = 12, not 9. Sadie cannot have scored 4 goals.

__

If we let s represent the number of goals Sadie scored, then 2s is the number Connor scored. Their total is ...

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