The battery standby duration (in hours) of a new model of cell phone is known to be normally distributed. Ten pieces of such new model of cell phone supplied from the manufacturer are randomly chosen and the actual standby durations are recorded as below:

48.2 47.8 45.6 47.2 49.3
51.2 44.2 45.4 49.2 43.6

(a) Calculate the unbiased estimates of population mean and standard deviation of battery standby duration (in hours) of the new cell phone.

(b) The manufacturer claimed that this new model of cell phone has the mean battery standby duration of longer than 46.5 hours. Test at 1% significance level if this claim is true.

Answer:

Step-by-step explanation:

7)  4*5 - 2*3 = answer

20-6 = 14

8)  5*4 - 2*(2*2) = answer

20 -8 = 12

Answer:

Step-by-step explanation:

A rational number can be written as a fraction of two integers.

√23 is irrational because we do not know what the square root of 23 is in terms of integers in a fraction.

104.42 is rational because it can be expressed as 10442/100 . We can express it as this because

104.42 * 1 = 104.42 * 100/100 = 10442/100, and multiplying something by 1 keeps it the same

√64 is rational because it is equal to 8, and 8/1 is equal to 8

49.396 with the 6 repeating is rational because we can express 49.39 as

49.39 * 1 = 49.39 * 100/100 = 4939/100, and we are then left with

49.396- 49.39 = 0.006 (with the 6 repeating). A repeating decimal can be expressed as x/9, with the x representing all values before the repetition begins multiplied by 10.

For example, 0.6 with the 6 repeating can be represented as 6/9. This is because 0.6 * 10 = 6, and we divide that by 9. Similarly, 0.006 with the 6 repeating can be represented by 0.06/9

We add the two fractions together to get

4939/100 + 0.06/9

multiply both fractions by the other's denominator to even them out and make the numerator of the second fraction an integer

(4939*9)/(100*9) + (0.06*100)/(9*100)

= 44451/900 + 6/900

= 44460/900

Assuming that the last number has only the digits given, that is rational because, similarly to 104.42, it can be multiplied by a power of 10 to result in (integer)/(integer), making it rational. If the dots represent infinite digits, then it is not rational because there are infinite digits that are not repeating, and there is no way to know the last digit, so it is impossible to write a fraction from it

Answer:

The 3 ses that we found are:

{4, 5, 6}

{64, 65, 66}

{124, 125, 126}

Step-by-step explanation:

3 consecutive numbers are written as:

n, (n + 1), (n + 2)

We know that the first one is a multiple of 4.

Then n is a multiple of 4:

n = k*4

where k is an integer.

The second one is a multiple of 5, then:

(n + 1) = j*5

where j is an integer.

The last one is a multiple of 6.

(n + 2) = p*6

where p is an integer.

We want to find 3 sets.

The first one is trivial:

n = 4

n + 1 = 5

n + 2 = 6

4 is a multiple of 4

5 is a multiple of 5

6 is a multiple of 6.

Now let's find a set that is not trivial.

First, remember that all the multiples of 5 end with a 0 or a 5,

Then we can look for a value n, that is multiple of 4, and that has a last units digit equal to 4 (then the next one will have a units digit and will be multiple of 5)

For example, 4*6 = 24

24 is a multiple of 4.

The next number is 24 + 1 = 25, which is multiple of 5.

The next number is 25 + 1 = 26, which is not multiple of 6.

So let's try again.

4*11 = 44, is a multiple of 4.

The next number is 44 + 1 = 45

45 is a multiple of 5.

The next number is 45 + 1 = 46, which is not multiple of 6

So we need to try with another set.

4*16 = 64, is a multiple of 4.

The next number is 64 + 1 = 65, which is multiple of 5.

The next number is 66, which is multiple of 6:

6*11 = 66

Then the set:

n = 64

n + 1 = 65

n + 2 = 66

Is a possible set.

Now we can keep trying this, we can see that the next set  has the numbers:

n = 4*31  = 124 is a multiple of 4.

The next number, is 124 + 1 = 125, which is a multiple of 5.

The next number is 125 + 1 = 126, which is multiple of 6

6*21 = 126

Then the set:

n = 124

n + 1 = 125

n + 2 = 126

Is another possible set.

The 3 ses that we found are:

{4, 5, 6}

{64, 65, 66}

{124, 125, 126}

Answer:

y = 4x -2

Step-by-step explanation:

y = 4x + b

6 = 4(2) + b

6 = 8 + b

-2 = b

Answer:

[tex]\sf m\angle A = 3x - 20^o = \bf 100^o [/tex]

[tex]\sf m\angle B = 2x = \bf 80^o [/tex]

[tex]\sf m\angle C = 2x - 15^o = \bf 65^o [/tex]

Step-by-step explanation:

A figure is given to us , in which two lines are parallel to each other. There are two transversals to the || lines . We know that the measure of a straight line is 180° . Therefore ,

[tex]\sf\longrightarrow \angle A +\angle B = 180^o [/tex]

Substitute the given values ,

[tex]\sf\longrightarrow 3x - 20^o + 2x = 180^o [/tex]

Simplify the RHS by adding the variables ,

[tex]\sf\longrightarrow 5x - 20^o = 180^o [/tex]

Add 20° to both sides ,

[tex]\sf\longrightarrow 5x = 180^o + 20^o [/tex]

Add the numbers in RHS ,

[tex]\sf\longrightarrow 5x = 200^o [/tex]

Divide both sides by 5 ,

[tex]\sf\longrightarrow \boxed{\blue{\sf x = 40^o}}[/tex]

Therefore ,

Answer:

00000000.1

Step-by-step explanation:

1+1=2-1%000.1

Answer:

1) -0.669

2) -0.669

3) 0.669

Step-by-step explanation:

Since we are subtracting or adding multipled of pi, we will either obtain 0.669 or -0.669 as our answer for each of the three different questions.

Cosine is the x-coordinate in our orderes pairs. If our point ends up on the right side of the y-axis, the cosine will be positive. If our point ends up on left side, it will be negative.

Choose a thetha (I'm going to choose it in degrees) in the first quadrant to help with a visual.

If theta=70:

1) then 180-70=110 which is in second quadrant, so our cosines will be opposite in value.

2) then 180+70=250 which is in third quadrant, so our cosines will be opposite in value.

3) then 4×180-70=720-70=650 =1(360)+290 which ends up in the 4th quadrant which means the consines will have the same value.

Answer:

(x-3) years

Step-by-step explanation:

We are given that

Age of Jonathan= x years

Sage is 7 years older than Jonathan

It means

Age of Sage=(x+7) years

We have to find the age of Sage 10 years ago.

10 Years ago,

Age of Jonathan=(x-10) years

Age of Sage=(x+7-10) years

Age of Sage=(x-3) years

Hence, 10 years ago, age of Sage =(x-3) years

Answer:

The quantity of loaves left in the bag is 3/4.

Step-by-step explanation:

Carlos bought a certain amount of loaves, put 1/4 of that amount on his tray and left the rest of the loaves in the bag. How many loaves did Carlos leave in the bag?

Quantity of loaves in tray is 1/4

So, the quantity of loaves in the bag is

[tex]1-\frac{1}{4}=\frac{3}{4}[/tex]

Answer:

a. The constant of proportionality is, 21

b. Tiana charges $94.50 for a job, so, c=94.50

from the given equation,

c = 21h

or, 94.50 = 21h

or, h = 94.50/21

or, h = 4.5

She babysit for 4.5 hours.

Answered by GAUTHMATH

c = 21h

94.50 = 21h

h = 94.50 ÷ 21

h = 4.5hours.

Therefore, Tiana spent 4½ hours babysitting.

Learn more: https://brainly.com/question/20986361?referrer=searchResults

Answer:

y=7x

Step-by-step explanation:

because y= 4x+3=7x

Answer:

12x+1

Step-by-step explanation:

8x+3+4x-2

8x+4x+3-2

Arranging Like terms

12x+1

Adding Like terms (8x+4x) and Substracting numbers ! ++- = - So we substrate it and in addition we don't change symbols so 3 is greatest number so we write + there !

Answer:

huh???

Step-by-step explanation:

how does that make sence

The answer is 59049.

Kuaaahahahahahahahah!

Answer:

3rd option

Step-by-step explanation:

There is a common ratio between consecutive terms , that is

r = - 6 ÷ 1 = 36 ÷ - 6 = - 216 ÷ 36 = - 6

To obtain a term in the sequence multiply the previous term by - 6

Then the recursive rule is

[tex]a_{n}[/tex] = - 6 . [tex]a_{n-1}[/tex]

Answer: 1*6°=6

1*(-6)^1=-6

1*(-6)^2=36

1*(-6)^3=-216

Answer:

704π

Step-by-step explanation:

V = π×r²×h

= π×8²×11

= 704π yd³

Answer:

23.56

Step-by-step explanation:

2([tex]\pi r^{2}[/tex]) + 2[tex]\pi[/tex]rh

2([tex]\pi[/tex] [tex]1.5^{2}[/tex])+ 2[tex]\pi[/tex](1.5)(1)

23.56

23.56 in² is the surface area

A solid object's surface area is a measurement of the overall space that the object's surface takes up.

Given

2(πr²) + 2πrh

2π( 1.5)²+ 2π(1.5)(1)

= 23.56 in²

To know more about surface area refer to:

https://brainly.com/question/16082274

#SPJ2

Answer:

Step 1: 1.5

Step 2: Plot the points (0, 1.5)

Step 3: 3, then 0.75

Step 4: Plot the points (1, 3) and (-1, 0.75)

Step 5: y=0

Step-by-step explanation:

Ur welcome and have a nice day :>

The initial value of the function f(x) = 3/2 (2)^x is 3/2

The function expression is given s:

f(x) = 3/2 (2)^x

Substitute 0 for x

f(0) = 3/2 (2)^0

Evaluate the exponent

f(0) = 3/2 * 1

Evaluate the product

f(0) = 3/2

Hence, the initial value of the function is 3/2

Read more about exponential functions at:

https://brainly.com/question/11464095

Answer:

1.33 & n - 6 = 0.75(t - 8)

Explanation:

Speed can be calculated as miles ÷ minutes

4 ÷ 3 = 1.33 and 8 ÷ 6 = 1.33 as well

Since we know the n and t, we can substitute one into the equation to find the other (substitute t = 8 into all four equations and see do we get n = 6)

You can do this with t = 4 and n = 3 as well

Answer:

you are a great woman removing the sum o saare and pa and pa to the lord and your life to you for drawing the sum o the streets

Answer:

Step-by-step explanation:

thats your problem learn how to pay attention lol

Answer:

4 / 663

Step-by-step explanation:

Given that :

Number of cards in a standard deck = 52

Number of 3's in s standard deck = 4 (each suit has one card each)

Number of 8's in a standard deck = 4 (each suit has one card each)

Probability, P = required outcome / Total possible outcomes

Choosing without replacement :

P(top card is a 3) = 4 / 52

P(second draw is 8) = 4 / 51

P(top card is a 3 and second is 8) :.

4/52 * 4/51 = 16 / 2652 = 4 / 663

Answer:

Step-by-step explanation:

Clyde has x crayons.

Amanda has y crayons.

The equation:

Answer:

Last answer.

Step-by-step explanation:

What I do is divide the terms by the previous terms, and if they all equal 1.5, that is your answer.

x+2y=4 ] × (-2) —> -2x-4y=-8

2x-3y=1

-2x-4y=-8

_________o_o___

–7y=–7 —> y =1

2x-3y=1 —> 2x -3(1)=1 —> 2x-3=1 —> 2x=1+3 —> 2x=4

x=4/2 —> x=2

(x,y) —> ( 2,1)

Answer:

x=1, x=2, x=3, x=4, x=5

Step-by-step explanation:

set each expression in the parenthesis equal to 0 to solve for the roots

Answer:

mark brainlist..............

Answer:

[tex]A = Pe ^{-0.03108 * t}[/tex]

Step-by-step explanation:

Note: these are typically two part questions...

you have the model and have to FIRST find a constant value "k"

once you have the "k" value you plug that into the model to finish the problem

[tex]A = Pe ^{-kt}[/tex] is a typical version of the continuous decay...

e is "e 2.717" not a variable "e"

so... step 1.. fink k

you are told that the 1/2 life is 22.3 years...

so lets assume that we started with 2 units of lead, and waited for it to decrease to 1 (1 is 1/2 of 2)

you would have

1 = 2[tex]e^{k * 22.3}[/tex]

.5 = [tex]e^{k * 22.3}[/tex]

ln(.5) = 22.3k ln(e)

ln(e) = 1

ln(.5) = 22.3k

ln(.5) = 22.3k ln(e)

[tex]\frac{ln(.5) }{22.3} = k[/tex]

[tex]\frac{\ln \left(0.5\right)}{22.3}=-0.03108[/tex] = k