Plz help me well mark brainliest if correct!....

Answer:

Step-by-step explanation:

What is it help

Approximately 47.72% of phones have a battery life of between 4.5 and 5.25 hours.

A standard deviation (or σ) is a measure of how dispersed the data is in relation to the mean. Low standard deviation means data are clustered around the mean, and high standard deviation indicates data are more spread out.

here, we have,

To determine the percentage of phones with a battery life between 4.5 hours and 5.25 hours, we need to find the area under the normal curve between those two points.

To do this, we can standardize the lower and upper limits of the range and use a table of the normal distribution to find the area.

The lower limit of the range, 4.5 hours, is 0.25 hours less than the mean of 5 hours. Since the standard deviation is 15 minutes, which is equal to 0.25 hours, the lower limit is 0.25 standard deviations below the mean.

The upper limit of the range, 5.25 hours, is 0.25 hours more than the mean of 5 hours. Since the standard deviation is 15 minutes, which is equal to 0.25 hours, the upper limit is 0.25 standard deviations above the mean.

The area under the normal curve between the lower and upper limits is therefore the area under the normal curve between -0.25 and 0.25 standard deviations.

Using a table of the normal distribution, we find that the area under the normal curve between -0.25 and 0.25 is approximately 0.4772.

Thus, about 47.72% of phones have a battery life between 4.5 hours and 5.25 hours.

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Answer: The answer is C, hope I helped :)

Step-by-step explanation:

A purchase of 10 tickets is at an expected loss of $0.857 to the person.

Option B) $8.57 loss is the right choice.

The expected gain or loss is a weighted average of the probability of the different gains or losses and the gains or losses.

We are asked to calculate the expected gain or loss for a participant who purchases 10 tickets for a raffle costing $1 each, with a prize of a telescope valued at $425. We are told that a total of 2980 tickets have been sold.

First, we calculate the expected gain or loss on 1 ticket,

= 425*(1/2980) + (-1)(1)

= 0.1426174496 - 1

= -0.857382550.

∴ A purchase of 1 ticket is at an expected loss of $0.857

Now, we multiply this by 10 to get the expected gain or loss for the person with 10 tickets.

= -0.857382550*10 = -8.57382550

∴ A purchase of 10 tickets is at an expected loss of $0.857 to the person. Option B) $8.57 loss is the right option.

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Answer:

a

Step-by-step explanation:

Answer:

.75 liters

Step-by-step explanation:

add a decimal point at the end of 750 and move it 3 places to the left because mili is one thousandth of a liter

Answer:

Since the calculated value of z=  -1.421 does not lie in the critical region z >

- 1.96 the null hypothesis is accepted and it is concluded that the treatments result in the same effect.

Step-by-step explanation:

1) Let the null and alternate hypothesis be

H0:  μa  − μb = 0  the treatments result in the same effect

against the claim

Ha: μa − μb ≠ 0   the treatments  do not result in the same effect

2) The significance level is set at 0.05

3) The critical region is z =  ± 1.96

4) The test statistic

Z= x1`-x2`/ sqrt [( s1²/n1+ s2²/n2)]

Here

x1`= 17             s1= 4               n1= 13

x2`= 19             s2= 3             n2= 12

5) Calculations

Z= x1`-x2`/ sqrt [( s1²/n1+ s2²/n2)]

z= 17-19/sqrt [( 16/13+ 9/12)]

z= -2/1.40739

z= -1.421

6) Conclusion

Since the calculated value of z=  -1.421 does not lie in the critical region z >

- 1.96 the null hypothesis is accepted and it is concluded that the treatments result in the same effect.

Answer:

The maximum lifetime a bulb can have and still be among the lowest 1% of all lifetimes is 572 hours.

Step-by-step explanation:

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

The lifetime of the bulbs is a normally distributed random variable with mean equal to 600 hours and standard deviation of 12 hours.

This means that [tex]\mu = 600, \sigma = 12[/tex]

What is the maximum lifetime a bulb can have (hrs) and still be among the lowest 1% of all lifetimes?

This is the 1st percentile of lifetimes, which is X when Z has a pvalue of 0.01, that is, X when Z = -2.327.

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]-2.327 = \frac{X - 600}{12}[/tex]

[tex]X - 600 = -2.327*12[/tex]

[tex]X = 572[/tex]

The maximum lifetime a bulb can have and still be among the lowest 1% of all lifetimes is 572 hours.

Answer:

cool and whats the question

Step-by-step explanation:

Answer:

The slope represents the change/rise is the yearly imcome based on age. The y-intercept is the amount that they make when they first get a job.

Step-by-step explanation:

Answer:

-3/-2

Step-by-step explanation:

because (x,y) the x coordinate is -3 and the y coordinate is -2

Answer:

length 5cm, width 4cm, door width 2/5cm or. 4cm, length 10 ft, width 7.5 ft

Answer:

30 ft²

Step-by-step explanation:

Area of trapezium = 1/2 (a + b)h

a = 6 ft , b = 9 ft , h = 4 ft

Area = 1/2 (6 + 9) 4

= 30 ft²

Answer:

D

Step-by-step explanation:

SAS IS YOUR ANSWER!

HOPE THISE HELPS

Answer:

angle 2 is 99

angle 7 is 81

Step-by-step explanation:

Angle 2 and the angle we are given are congruent because they are vertical.

Angle 7 and the angle we are given form a line, so they add up to 180.

180-99 = 81

X= -3 this solution is extraneous

X= 5 this solution is valid

Answer:

72

Step-by-step explanation:

72/8 = 9

Answer:

x=72

Step-by-step explanation:

Step- by- step Explanation

Answer:

1. 142 in.²

2. 190 cm²

Step-by-step explanation:

Both solids are rectangular prisms.

Surface area of a rectangular prism = 2(LW + LH + HW)

1. L = 7 in.

W = 3 in.

H = 5 in.

Plug ok the values into the formula

Surface area = 2(7*3 + 7*5 + 5*3)

= 142 in.²

2. L = 10 cm

W = 3 cm

H = 5 cm

Plug ok the values into the formula

Surface area = 2(10*3 + 10*5 + 5*3)

= 190 cm²

Answer:

Step-by-step explanation:

10

Answer:

Step-by-step explanation:

5 mph

Answer:

answer is A

Step-by-step explanation:

180-140=40

Answer:

Dependent

Step-by-step explanation:

When the probability is AND, it is dependent. You *have* to get the A outcome for A and B to be valid.

Answer:

There are 2 modes.

Step-by-step explanation:

Modes are the numbers we see most. There can be more than one mode or none at all.

Answer:

a = - 1

b = - 9

c = 9

d = 3

e = 3

f = 2

g = 3/2

Step-by-step explanation:

For a;

6 - 2x = - (2x - 6)

For b;

-1 * 9 = - 9

For x ;

3x + (-9) = 3x - 9

3x - 9 = d(x - e)

Factorizing :

3(x - 3)

d = 3 ; e = 3

2x - 6 = f(x - 3)

Factorize :

2x - 6 = 2(x - 3)

3(x - 3) / 2(x - 3)

g = 3/2

Answer:

23.6

Step-by-step explanation:

Answer: 23.6

Step-by-step explanation:

Answer:

135in^3

Step-by-step explanation:

Answer:

3

Step-by-step explanation:

Answer:

726

Step-by-step explanation:

Here p = k / q², and 24 = k / 121, or k = 2904

Then p = 2904 / q²

If q = 2, p = 2904 /4 = 726

Answer:

p = 12 × 11²

Step-by-step explanation:

By question,

=> p ∝ 1/q²

=> p = k/q²

=> 24 = k/11²

=> k = 24 * 11²

=> p = k/q²

=> p = 24*11²/2

=> p = 12 × 11²

Answer:

49.1636363636

Step-by-step explanation:

Answer:

y = 7

Step-by-step explanation:

Let the equation of the line is,

y = mx + b

Here, m = Slope of the line

b = y-intercept

Line passes through two points (0, 7) and (-2, 7)

Therefore, slope of the line will be,

m = [tex]\frac{y_2-y_1}{x_2-x_1}[/tex]

m = [tex]\frac{7-7}{0+2}[/tex]

m = 0

If the slope of a line is 0 then the graph of the line will be parallel to x-axis.

By substituting the value of slope in the equation,

Equation of the line will be,

y = 0(x) + b

y = b

Since, the given line passes through (0, 7),

Equation of the line will be,

y = 7