Please help me out with these questions :

Answer:

please which level is this

and also is it core maths or elective math

Answer:

a) 1186

b) Between 1031 and 1493.

c) 160

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.

Normally distributed with mean of 1262 and a standard deviation of 118.

This means that [tex]\mu = 1262, \sigma = 118[/tex]

a) Determine the 26th percentile for the number of chocolate chips in a bag. ​

This is X when Z has a p-value of 0.26, so X when Z = -0.643.

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

[tex]-0.643 = \frac{X - 1262}{118}[/tex]

[tex]X - 1262 = -0.643*118[/tex]

[tex]X = 1186[/tex]

(b) Determine the number of chocolate chips in a bag that make up the middle 95% of bags.

Between the 50 - (95/2) = 2.5th percentile and the 50 + (95/2) = 97.5th percentile.

2.5th percentile:

X when Z has a p-value of 0.025, so X when Z = -1.96.

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

[tex]-1.96 = \frac{X - 1262}{118}[/tex]

[tex]X - 1262 = -1.96*118[/tex]

[tex]X = 1031[/tex]

97.5th percentile:

X when Z has a p-value of 0.975, so X when Z = 1.96.

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

[tex]1.96 = \frac{X - 1262}{118}[/tex]

[tex]X - 1262 = 1.96*118[/tex]

[tex]X = 1493[/tex]

Between 1031 and 1493.

​(c) What is the interquartile range of the number of chocolate chips in a bag of chocolate chip​ cookies?

Difference between the 75th percentile and the 25th percentile.

25th percentile:

X when Z has a p-value of 0.25, so X when Z = -0.675.

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

[tex]-0.675 = \frac{X - 1262}{118}[/tex]

[tex]X - 1262 = -0.675*118[/tex]

[tex]X = 1182[/tex]

75th percentile:

X when Z has a p-value of 0.75, so X when Z = 0.675.

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

[tex]0.675 = \frac{X - 1262}{118}[/tex]

[tex]X - 1262 = 0.675*118[/tex]

[tex]X = 1342[/tex]

IQR:

1342 - 1182 = 160

This question is incomplete, the complete question is;

A student bought a smart-watch that tracks the number of steps she walks throughout the day. The table shows the number of steps recorded (t) minutes after 3:00 pm on the first day she wore the watch.

t (min)       0          10          20         30         40

Steps   3,288    4,659    5,522    6,686    7,128

a) Find the slopes of the secant lines corresponding to the given intervals of t.

1) [ 0, 40 ]

11) [ 10, 20 ]

111) [ 20, 30 ]

b) Estimate the student's walking pace, in steps per minute, at 3:20 pm by averaging the slopes of two secant lines from part (a). (Round your answer to the nearest integer.)

Answer:

a)

1) for [ 0, 40 ], slope is 96

11) for [ 10, 20 ],  slope is 86.3

111) for  [ 20, 30 ], slope is 116.4

b) the student's walking pace is 101 per min

Step-by-step explanation:

Given the data in the question;

t (min)       0          10          20         30         40

Steps   3,288    4,659    5,522    6,686    7,128

SLOPE OF SECANT LINES

1) [ 0, 40 ]

slope =  ( 7,128 - 3,288 ) / ( 40 - 0

= 3840 / 40 = 96

Hence slope is 96

11)  [ 10, 20 ]

slope = ( 5,522 - 4,659 ) / ( 20 - 10 )

= 863 / 10 = 86.3

Hence slope is 86.3

111)  [ 20, 30 ]

slope = ( 6,686 - 5,522 ) / ( 30 - 20 )

= 1164 / 10 = 116.4

Hence slope is 116.4

b)

Estimate the student's walking pace, in steps per minute, at 3:20 pm by averaging the slopes of two secant lines from part .

Since this is recorded after 3:00 pm

{ 3:20 - 3:00 = 20 }

so t = 20 min

so by average;

we have ( [ 10, 20 ] + [ 20, 30 ] ) /2

⇒ ( 86.3 + 116.4 ) / 2

= 202.7 /2

= 101.35 ≈ 101

Therefore, the student's walking pace is 101 per minutes

Answer:

Probability[Number of people from church] = 0.26 (Approx.)

Step-by-step explanation:

Given:

Total number of adult in survey = 1,033

Missing information:

Number of people from church = 269

Find:

Probability[Number of people from church]

Computation:

Probability of an event = Number of favourable outcomes / Number of total outcomes

Probability[Number of people from church] = Number of people from church / Total number of adult in survey

Probability[Number of people from church] = 269 / 1,033

Probability[Number of people from church] = 0.2604

Probability[Number of people from church] = 0.26 (Approx.)

Answer:

1/5

Step-by-step explanation:

Probability calculates the likelihood of an event occurring. The likelihood of the event occurring lies between 0 and 1. It is zero if the event does not occur and 1 if the event occurs.

For example, the probability that it would rain on Friday is between o and 1. If it rains, a value of one is attached to the event. If it doesn't a value of zero is attached to the event.

probability that the ticket drawn has a number which is a multiple of 5 =

Number of tickets that are a multiple of 5 / total number of tickets

Multiple of 5 = 5, 10, 15, 20

there would be 4 tickets that would be a multiple of 5

= 4/20

To transform to the simplest form. divide both the numerator and the denominator by 4

= 1/5

Answer:

see below

Step-by-step explanation:

[tex] \displaystyle AB = DE[/tex]

[given]

[tex] \displaystyle \boxed{BC = EF}[/tex]

[given]

[tex] \displaystyle AB + BC = AC[/tex]

[segment addition Postulate]

[tex] \displaystyle \boxed{DE+ EF=DF}[/tex]

[segment addition Postulate]

[tex] \rm\displaystyle DE+ BC = AC \: \: \text{and} \: \: DE+ BC = DF[/tex]

[Substitution Property of Equality]

[tex] \displaystyle \boxed{AE= DE}[/tex]

[Proven]

Given:

Size of a red blood cell = 0.000007 m

Size of a plant cell = 0.0000127 m

To find:

The comparison of these two values.

Solution:

We have,

Size of a red blood cell = 0.000007 m

Size of a plant cell = 0.0000127 m

Clearly, [tex]0.0000127>0.000007[/tex]. Now, the difference between these two values is:

[tex]0.0000127-0.000007=0.0000057[/tex]

Therefore, the size of a plant cell is 0.0000057 m more than the size of a red blood cell.

Answer:

0.5587 = 55.87% probability that the sample mean would differ from the true mean by less than 1.1 dollars.

Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

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.

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

The cost of 5 gallons of ice cream has a variance of 64 with a mean of 34 dollars during the summer.

This means that [tex]\sigma = \sqrt{64} = 8, \mu = 34[/tex]

Sample of 38

This means that [tex]n = 38, s = \frac{8}{\sqrt{38}}[/tex]

What is the probability that the sample mean would differ from the true mean by less than 1.1 dollars ?

P-value of Z when X = 34 + 1.1 = 35.1 subtracted by the p-value of Z when X = 34 - 1.1 = 32.9. So

X = 35.1

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

By the Central Limit Theorem

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

[tex]Z = \frac{35.1 - 34}{\frac{8}{\sqrt{38}}}[/tex]

[tex]Z = 0.77[/tex]

[tex]Z = 0.77[/tex] has a p-value of 0.77935

X = 32.9

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

[tex]Z = \frac{32.9 - 34}{\frac{8}{\sqrt{38}}}[/tex]

[tex]Z = -0.77[/tex]

[tex]Z = -0.77[/tex] has a p-value of 0.22065

0.77935 - 0.22065 = 0.5587

0.5587 = 55.87% probability that the sample mean would differ from the true mean by less than 1.1 dollars.

Answer:

The 98% confidence interval for the mean amount spent on their child's last birthday gift is between $40.98 and $43.02.

Step-by-step explanation:

We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.

The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So

df = 24 - 1 = 23

98% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 23 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.98}{2} = 0.99[/tex]. So we have T = 2.5

The margin of error is:

[tex]M = T\frac{s}{\sqrt{n}} = 2.5\frac{2}{\sqrt{24}} = 1.02[/tex]

In which s is the standard deviation of the sample and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 42 - 1.02 = $40.98.

The upper end of the interval is the sample mean added to M. So it is 42 + 1.02 = $43.02.

The 98% confidence interval for the mean amount spent on their child's last birthday gift is between $40.98 and $43.02.

Answer:

The number is 9.5

Step-by-step explanation:

Look at the picture above, it explains everything

Answer:

A

Step-by-step explanation:

From f(x) to k(x), the graphed parabola is stretched and wider.

Answer: Choice B) Vertically compressed by a factor of 8.

Explanation:

Consider a point like (8,64) which is on f(x).

If we plug in x = 8 into k(x), then we would get k(8) = 8. The old output y = 64 is now y = 8. This is an example of a vertical compression of 8. It's 8 times smaller in the vertical direction compared to what it used to be. This is because the k(x) outputs are 1/8 those of the f(x) outputs.

Effectively we have k(x) = (1/8)*f(x).

Another example would be x = 16 leading to y = 256 on f(x). For k(x), we have x = 16 lead to y = 32

Refer to the graph below.

Answer:

a) -0.94

b) 0.3472

c) -2.327, 2.327

Step-by-step explanation:

A claim is made that the proportion of 6-10 year-old children who play sports is not equal to 0.5.

At the null hypothesis, we test if the proportion is of 0.5, that is:

[tex]H_0: p = 0.5[/tex]

At the alternative hypothesis, we test if the proportion is different from 0.5, that is:

[tex]H_1: p \neq 0.5[/tex]

The test statistic is:

[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]

In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.

0.5 is tested at the null hypothesis:

This means that [tex]\mu = 0.5, \sigma = \sqrt{0.5*(1-0.5)} = 0.5[/tex]

A random sample of 551 children aged 6-10 showed that 48% of them play a sport.

This means that [tex]n = 551, X = 0.48[/tex]

(a) Calculate the value of the test statistic used in this test.

[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]

[tex]z = \frac{0.48 - 0.5}{\frac{0.5}{\sqrt{551}}}[/tex]

[tex]z = -0.94[/tex]

So the answer is -0.94.

(b) Use your calculator to find the P-value of this test.

The p-value of the test is the probability that the sample proportion differs from 0.5 by at least 0.02, which is P(|z| > 0.94), which is 2 multiplied by the p-value of Z = -0.94.

Looking at the z-table, z = -0.94 has a p-value of 0.1736.

2*0.1736 = 0.3472, so 0.3472 is the answer to option b.

(c) Use your calculator to find the critical value(s) used to test this claim at the 0.02 significance level.

Two-tailed test(test if the mean differs from a value), Z with a p-value of 0.02/2 = 0.01 or 1 - 0.01 = 0.99.

Looking at the z-table, this is z = -2.327 or z = 2.327.

Answer:

45

Step-by-step explanation:

What are you trying to solve for?

[tex]824381 + 1654 = - 121[/tex]

The sample statistic that must have changed after the correction was made is mean. Because mean is based on all the observation in the data. So changing any value in the data will impact mean.

Changing the highest salary in the data will have no impact on median because median lies at the center of data.

Changing the highest salary in the data will have no impact on mode because mode is the most frequently occurring value in the data.

Changing the highest salary in the data will have no impact on minimum because minimum is the smallest value in the data.

Hence the only statistic which will change is mean.

Answer: A-Mean

Step-by-step explanation:

A.) Mean

B.) Median

C.)  Mode

D.)  Minimum

Explanation:

The range is the set of y outputs of a relation. So we just list the y coordinates of the points shown.

We could sort the values to get {-1, 4, 11, 13}, but order doesn't matter in a set. So this step is optional.

Answer:

200000

Step-by-step explanation:

29563487

Answer:

The new volume is 3n^2+2n inches greater.

Step-by-step explanation:

Volume of a cube = s^3 where s is side of cube

Original volume = n^3

Volume of a Rectangular Prism = LBH

New Volume = (n+1)(n+2)(n)= n^3+3n^2+2n

DIfference = New- original = 3n^2+2n

9514 1404 393

Answer:

  (a) one parallelogram

  (b) opposite sides are 3 inches and 4 inches. Opposite angles are 45° and 135°

  (c) yes, all side lengths can be determined, see (b)

Step-by-step explanation:

Opposite sides of a parallelogram are the same length, so if one side is 3 inches, so is the opposite side. Similarly, if one side is 4 inches, so is the opposite side. If sides have different lengths, they must be adjacent sides. The given numbers tell us the lengths of all of the sides.

The 4 inch sides are adjacent to the 3 inch sides. Thus the angle between a 4 inch side and a 3 inch side must be 45°. Opposite angles are congruent, and adjacent angles are supplementary, so specifying one angle specifies them all.

Only one parallelogram can be formed with these sides and angles. (The acute angle can be at the left end or the right end of the long side. This gives rise to two possible congruent orientations of the parallelogram. Because these are congruent, we claim only one parallelogram is possible. Each is a reflection of the other.)

Answer:

Point A:

(3, -5)

Point B:

(6, -2)

Point C:

(5, -7)

Step-by-step explanation:

Background:

Moving to the right means adding to the x.

Moving to the left means subtracting from the x.

Moving up means adding to the y.

Moving down means subtracting from the y.

So take each point and add 3 to the x, and subtract 4 from they y.

Point B:

(3, 2) → (6, -2)

Point A:

(0, -1) → (3, -5)

Point C:

(2, -3) → (5, -7)

Answer:

B, C, and E

Step-by-step explanation:

9514 1404 393

Answer:

  assumed accuracy from overly precise numbers

Step-by-step explanation:

Except when counting large sums of money or considering definitions, most real-world numbers are not accurate beyond about 6 significant figures. When considering survey or sample results, the accuracy can be considerably less than that, often not even good to 3 significant figures. (Margin of error is usually some number of percentage points greater than 1.)

Expressing the given ratios to 10 significant figures substantially misstates their accuracy. (10^-9 television is less than 1 day's accumulated dust).

Answer:

[tex]x = \sqrt{-2} = 2i[/tex]

Step-by-step explanation:

[tex]5x^2-2=-12[/tex]

[tex]5x^2 =-10[/tex]

[tex]x^2 =-2[/tex]

[tex]x = \sqrt{-2} = 2i[/tex]

Answer:

The volume of the cube is 0.171 cubic inches.

Step-by-step explanation:

The volume of a cube given by :

[tex]V=s^3[/tex]

Where

s is the length of one of the sides.

We need to find the volume of the sugar cube if its side is 5/9 inches per side.

So,

[tex]V=(\dfrac{5}{9})^3\\\\V=0.171\ inches^3[/tex]

So, the volume of the cube is 0.171 cubic inches.

9514 1404 393

Answer:

  4.1

Step-by-step explanation:

x is the short leg of a right triangle with hypotenuse 8.8 cm and longer leg 7.8 cm. Its measure is found using the Pythagorean theorem:

  x^2 +7.8^2 = 8.8^2

  x^2 = 77.44 -60.84 = 16.60

  x = √16.6

  x ≈ 4.1

Hello,

answer f: conjugate

if all coefficients are real and a+ib a zero, its conjgate a-ib is also a zero.

Answer:

The value of A is 5

......

[tex]\huge{\boxed{\boxed { ⎆ Answer :- }}} \ [/tex]

[tex](x + a)(x - a) = {x}^{2} - 25[/tex]

Use, the algebraic identity ↦

[tex](a + b)(a - b) = {a}^{2} - {b}^{2} [/tex]

So,

[tex](x + a)(x - a) = {x}^{2} - 25 \\ \\ ⟹ \sqrt{25} = 5[/tex]

↦So, the value of a is 5.

ʰᵒᵖᵉ ⁱᵗ ʰᵉˡᵖˢ

꧁❣ ʀᴀɪɴʙᴏᴡˢᵃˡᵗ2²2² ࿐