It says I need too put 20 characters in too ask the question so ignore this part

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:

128 for 4.99

64 for 2.99 times 2 is more than 4.99.

12 oz. for 0.99 is also more than 4.99.

Answer:

A. 18 calls

B. 0.9

C. 20

Step-by-step explanation:

Number of representatives=2,

Number of extension lines=2,

Average calls each representative can accommodate per hour = 15 calls,

Arrival rate per hour = 30 calls

(a) 90% of the arrival rate = 0.09 × 20 = 18 calls

To handle 18 calls immediately, 18 extension lines should be used

(b) Probability is given by number of possible outcomes ÷ number of total outcomes

Number of possible outcomes = 18, number of total outcomes = 20

Probability (call will receive busy signal) = 18/20 = 0.9

(c) For one extension line, numbers of calls to receive busy signal = 20 - 10 = 10 calls

Number of calls to receive busy signal for the current telephone system with two extension lines = 2 × 10 = 20 calls

Answer:

a. $10  

b. 10.46  

c. 10.46  

d. 0.096

Step-by-step explanation:

Let us take a nominal square of area 25 cm².

So, in this question, we can say that:-

a. The length of one of its sides will be less than 5 cm.

b. Its perimeter will be less than 20 cm.

Hope it helps :)

Step-by-step explanation:

area= 25cm squared

length of one side = 5cm as 5*5 =25

perimeter= 5*4= 20cm

But since the area is less than 25cm squared

we can say that the length of one side is less than 5cm and we can also say that the length of the perimeter is less than 20cm.

Hope this helps.

Answer:

1/6 < 2/11

Step-by-step explanation:

1/6 = 2/12

2/11 >2/12

So that means 1/6 < 2/11

Answer:  1/6 < 2/11

This is the same as saying 11/66 < 12/66

===========================================================

Explanation:

1/6 is the same as 11/66 when multiplying top and bottom by 11.

2/11 is the same as 12/66 when multiplying top and bottom by 6.

The 6 and 11 multipliers are from the original denominators (just swapped).

We can see that 11/66 is smaller than 12/66, simply because 11 < 12, so that means 1/6 is smaller than 2/11

-----------------

Here's one way you could list out the steps

11 < 12

11/66 < 12/66

1/6 < 2/11

------------------

Here's another way to list out the steps. First assume that 1/6 and 2/11 are equal. Cross multiplication then leads to

1/6 = 2/11

1*11 = 6*2

11 = 12

Which is false. But we can fix this by replacing every equal sign with a less than sign

1/6 < 2/11

1*11 < 6*2

11 < 12

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Yet another way to see which is smaller is to use your calculator or long division to find the decimal form of each value

1/6 = 0.1667 approximately

2/11 = 0.1818 approximately

We see that 0.1667 is smaller than 0.1818, which must mean 1/6 is smaller than 2/11.

Answer:

the car travels 10km then 15km 60* north of east

Step-by-step explanation:

Answer:

x = ±i√2

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Equality Properties

Multiplication Property of Equality

Division Property of Equality

Addition Property of Equality

Subtraction Property of Equality

Algebra II

Imaginary root i

Step-by-step explanation:

Step 1: Define

Identify

5x² - 2 = -12

Step 2: Solve for x

( solution at pic)

Answer:

0.1512 = 15.12% probability that fewer than four tornadoes occur in a three-week period.

Step-by-step explanation:

In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:

[tex]P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}[/tex]

In which

x is the number of sucesses

e = 2.71828 is the Euler number

[tex]\mu[/tex] is the mean in the given interval.

In a given region, the number of tornadoes in a one-week period is modeled by a Poisson distribution with mean 2

Three weeks, so [tex]\mu = 2*3 = 6[/tex]

Calculate the probability that fewer than four tornadoes occur in a three-week period.

This is:

[tex]P(X < 4) = P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3)[/tex]

In which

[tex]P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}[/tex]

[tex]P(X = 0) = \frac{e^{-6}*6^{0}}{(0)!} = 0.0025[/tex]

[tex]P(X = 1) = \frac{e^{-6}*6^{1}}{(1)!} = 0.0149[/tex]

[tex]P(X = 2) = \frac{e^{-6}*6^{2}}{(2)!} = 0.0446[/tex]

[tex]P(X = 3) = \frac{e^{-6}*6^{3}}{(3)!} = 0.0892[/tex]

Then

[tex]P(X < 4) = P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3) = 0.0025 + 0.0149 + 0.0446 + 0.0892 = 0.1512[/tex]

0.1512 = 15.12% probability that fewer than four tornadoes occur in a three-week period.

Answer:

He remained with 25 goats.

Step-by-step explanation:

35 - 10 = 25

Hope this helps.

Answer:

He remained with 25 goats

Step-by-step explanation:

35 - 10 = 25

Answer:

= x^2 + 3 + √3x^2 - 1

Step-by-step explanation:

Remove parentheses: (a) = a

= x^2 + 3 + √x . 3x - 1

x . 3x = 3x^2

= x^2 + 3 + √3x^2 - 1

Answer:

3.15 seconds is the answer.

Explanation

when the ball touches the ground, h =0

hence,

0=255-21t-16t²

16t²+21t-225=0

here a=16 ,b=21, c= -225

[tex]t= \frac{ - b± \sqrt{ {b }^{2} - 4ac} }{2a} \\ \\ t= \frac{ - 21± \sqrt{ {21}^{2} - 4 \times 16 \times - 225} }{2 \times 16} \\ = \frac{ - 21 ± \sqrt{441 - ( - 14400)} }{32} \\ = \frac{ - 21± \sqrt{14841} }{32} \\ = \frac{ - 21±121.82}{32} \\ \\ t = \frac{ - 21 + 121.82}{32} \: or \: \: t = \frac{ - 21 - 121.82}{32} \\ t = 3.15 \: \: or \: \: t = - 4.46[/tex]

time cannot be negative, hence t = -4.46 can be avoided

The ball takes 3.15 seconds to hit the ground.

Answer:

x=70

Step-by-step explanation:

First, we know that the mode is the number that is the most common. As each value in the set so far only has one of each number, we know that x must be one of the current numbers, making that the mode.

Next, because x is the mode and has to be the median as well, and our number line so far is

(10, 70, 80, 120), x must be either 70 or 80 to make it the median. This is because if x is 10 or 120, we would end up with (10, 10, 70, 80, 120) with 70 as the median or (10, 70, 80, 120, 120) with 80 as the median.

Finally, to calculate the mean, we have

mean = sum / count

The mean must be x, as it is equal to the mode, so we have

x = (10+70+80+120 + x)/5 (as there are 5 numbers including x)

multiply both sides by 5 to remove the denominator

5 * x = 10+70+80+120+x

5 * x = 280 + x

subtract x from both sides to isolate the x and the coefficient

4 * x = 280

divide both sides by 4 to get x

x= 70

We see that x is 70 or 80 and is one of the current numbers, checking off all boxes.

9514 1404 393

Answer:

  p > 3

Step-by-step explanation:

  3p -4 -8p < -19 . . . . . . given

  -5p -4 < - 19 . . . . . . . . collect terms

  -5p < -15 . . . . . . . . . . . add 4

  p > 3 . . . . . . . . . . . . . . divide by -5 (reverses the inequality symbol)

Answer:

Step-by-step explanation:

this is the famous dirt formula,  :P  I made it up   :D

D=rt    ( notice it looks like   Dirt  , kinda,  but it also means it dirt simple )

D= distance

r = rate  ( think speed or how fast)

t = time  ( in what ever units of time you want to use, seconds, minutes, hours )

13:28 - 11:20 = 128 minutes ( b/c the question is asking in MPH convert to hours)   2.4666667 hours

210 miles =  r * 2.46666667

210 / 2.46666667 = r   ( in MPH) ( does anyone else find it odd that they are saying miles in London instead of kilometers? :/ )

85.135 MPH = rate

so no, not even close to 104 MPH  :/  

Answer:

Average speed is 98 mph

Step-by-step explanation:

[tex]\frac{distance (miles)}{time (hours)}[/tex] = speed [tex]\frac{mile}{hours}[/tex]  (miles per hour is a ratio)

The time is 2 hours and 8 minutes.

[tex]\frac{8}{60}[/tex] = .13333 ( 8 minutes / 60 minutes in a hour)

So time is 2.133333 hours .

Divide the distance 210 by the time 2.13333 and get the speed.

Its 98.437..

Round to 98 miles per hour.

The solution for set F(x) is -1

Answer:

The first mechanic charged $ 85 an hour, and the second mechanic charged $ 55 an hour.

Step-by-step explanation:

Given that two mechanics worked on a car, and the first mechanic worked for 10 hours, and the second mechanic worked for 5 hours, and together they charged a total of $ 1125, to determine what was the rate charged per hour by each mechanic if the sum of the two rates was $ 140 per hour, the following calculation must be performed:

1125/15 = X

75 = X

80 x 10 + 60 x 5 = 800 + 300 = 1100

85 x 10 + 55 x 5 = 850 + 275 = 1125

Therefore, the first mechanic charged $ 85 an hour, and the second mechanic charged $ 55 an hour.

Answer: 75%

Step-by-step explanation:

Answer:

Length = 14 m, Width = 7 m

Step-by-step explanation:

Let the length is l and width is b.

Width, b = l-7

Area of the rectangle, A = 98 m²

We know that, the area of a rectangle is as follow :

[tex]A=lb[/tex]

So,

[tex]98=l(l-7)\\\\98=l^2-7l\\\\l^2-7l-98=0\\\\l^2+7l-14l-98=0\\\\l(l+7)-14(l+7)=0\\\\l=14,-7[/tex]

Length can't be negative. So,

Width, b = 14-7 = 7 m

So, the dimensions of the rectangle are 14 m and 7 m respectively.

Answer:

Step-by-step explanation:

a) 52 is divisible by 4 and 5 - 2 = 3

b) 63 is divisible by 9 and 3*2 = 6 -> ten digit

c) 50 is divisible by 10 and 5 + 0 = 5

d) 72 is divisible by 6 and 7*2 = 14

Answer:

The 95% confidence interval for the proportion of students who work out 4 or more times a week is (0.2432, 0.3568).

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.

[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

In which

z is the z-score that has a p-value of [tex]1 - \frac{\alpha}{2}[/tex].

In a random sample of 250 students, we found that 75 work out 4 or more times a week.

This means that [tex]n = 250, \pi = \frac{75}{250} = 0.3[/tex]

95% confidence level

So [tex]\alpha = 0.05[/tex], z is the value of Z that has a p-value of [tex]1 - \frac{0.05}{2} = 0.975[/tex], so [tex]Z = 1.96[/tex].

The lower limit of this interval is:

[tex]\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.3 - 1.96\sqrt{\frac{0.3*0.7}{250}} = 0.2432[/tex]

The upper limit of this interval is:

[tex]\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.3 + 1.96\sqrt{\frac{0.3*0.7}{250}} = 0.3568[/tex]

The 95% confidence interval for the proportion of students who work out 4 or more times a week is (0.2432, 0.3568).

Answer:

For the perimeters, x must be equal to 2.

For the areas, it is either undefined, or something.

Step-by-step explanation:

You can first find the perimeters for both sides.

For the left shape, we add the two sides of 6 and x + 4 to get x + 10.

Then we multiply x + 10 by 2 because there are 4 sides, and we only got 2 sides.

The perimeter of the first shape is 2x + 20.

The second shape can be solved by doing the same thing by adding 2 and 3x + 4 to get 3x + 6.

3x + 6 times 2 is 6x + 12.

The second perimeter is 6x + 12.

If both sides are supposed to be equal, then we can write these two expressions we solved for like:

6x + 12 = 2x + 20.

Subtraction property of equality

6x + 12 - 12 = 2x + 20 - 12

Simplify

6x = 2x + 8

Again

6x - 2x = 2x - 2x + 8

Simplify

4x = 8

Division property of equality

4/4x = 8/4

Simplify

x = 2

So if x = 2, the perimeters will be the same.

You can confirm this by plugging it back into either equation.

For the areas, we just multiply the length and width for both shapes, so we get

6(x+4)  =  2(3x+4)

Since they are supposed to be equal.

We simplify and get

6x + 24 = 6x + 8

We know this is false and is not possible, since we can remove the 6x because it is on both sides.

We also know that 24 is not equal to 8 (who thought!)

:D

24 ≠ 8

So it is undefined or whatever you call it.

Answer:

The zeroes of f(x) = (x-7)(x+8) are 7 and -8.

Step-by-step explanation:

You have to figure out what makes each of the equal to zero.

Step 1 : Make the 2 equations both equal 0.

x-7 = 0

x+8 = 0

Step 2: Solve for x

x-7 = 0

x=7

x+8 = 0

x=-8

So 7 and -8 are both zeroes of this function.

The answer is D

Hope that was fast enough

Answer:

0.3758 = 37.58% probability that at most one of her first 10 arrows hits the target

Step-by-step explanation:

For each shot, there are only two possible outcomes. Either they hit the target, or they do not. The probability of a shot hitting the target is independent of any other shot, which means that the binomial probability distribution is used to solve this question.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.

[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]

And p is the probability of X happening.

Each arrow with a probability 0.2

This means that [tex]p = 0.2[/tex]

First 10 arrows

This means that [tex]n = 10[/tex]

What is the probability that at most one of her first 10 arrows hits the target?

This is:

[tex]P(X \leq 1) = P(X = 0) + P(X = 1)[/tex]

So

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

[tex]P(X = 0) = C_{10,0}.(0.2)^{0}.(0.8)^{10} = 0.1074[/tex]

[tex]P(X = 1) = C_{10,1}.(0.2)^{1}.(0.8)^{9} = 0.2684[/tex]

Then

[tex]P(X \leq 1) = P(X = 0) + P(X = 1) = 0.1074 + 0.2684 = 0.3758[/tex]

0.3758 = 37.58% probability that at most one of her first 10 arrows hits the target

Answer:

In general gf(x) is not equal to fg(x)

Some pairs of functions cannot be composed. Some pairs of functions can be composed only  for certain values of x.

Only with they can be composed some values of x are the ranges of g(x) and f(x) are the same, and their domains are also the same. Or else lies inside it.

Step-by-step explanation:

g(x) = 3x + 6 - 8, f(x) = √x.

The domain of a composed function is either the same as the domain of the first function, or  else lies inside it

The range of a composed function is either the same as the range of the second function, or else lies inside it.

Or vice versa

Now only positive numbers, or zero, have real square roots. So g is defined only for numbers

greater than or equal to zero. Therefore g(f(x)) can have a value only if f(x) is greater than or

equal to zero. You can work out that

f(x) ≥ 0 only when x ≥3/2

.

Answer:

6.09 is the answer rounded to nearest hundredths.

Step-by-step explanation:

It gives you n=150, p=0.55, and q=1-p.

If p=0.55 and q=1-p, then by substitution property we have q=1-0.55=0.45.

It ask you to evaluate the expression sqrt(npq).

So npq means find the product of 150 and 0.55 and 0.45. So that is 150(0.55)(0.45)=37.125.

The sqrt(npq) means we need to find the square root of that product. So sqrt(37.125)=6.093 approximately .