Answer: -11
Step-by-step explanation:
4(-2)-3
-8-3
=-11
Whales have one of the longest gestation periods of any mammal. According to a website, the mean gestation period for a whale is 15 months. Assume the distribution of gestation periods is Normal with a standard deviation of 12 months
a. Find the standard score associated with a gestation period of 13.8 months
b. Using the Empirical Rule and your answer to part a, what percentage of whale pregnancies will have a gestation period between 13.8 and 15 months?
c. Would it be unusual for a whole to have a gestation period of 21 months? Why or why not?
The standard score associated with a gestation period of 13.8 months is __________.
Answer:
a) The standard score associated with a gestation period of 13.8 months is of [tex]Z = -1[/tex]
b) 34% of whale pregnancies will have a gestation period between 13.8 and 15 months.
c) Since when [tex]X = 21[/tex], [tex]Z = 5 \geq 2[/tex], it would be unusual for a whale to have a gestation period of 21 months.
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
Approximately 68% of the measures are within 1 standard deviation of the mean.
Approximately 95% of the measures are within 2 standard deviations of the mean.
Approximately 99.7% of the measures are within 3 standard deviations of the mean.
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 zscore 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 pvalue, we get the probability that the value of the measure is greater than X.
If [tex]Z \geq 2[/tex] or [tex]Z \leq -2[/tex], the measure X is considered to be unusual.
According to a website, the mean gestation period for a whale is 15 months. Assume the distribution of gestation periods is Normal with a standard deviation of 1.2 months.
I corrected to 1.2 because it is what makes sense considering the questions.
This means that [tex]\mu = 15, \sigma = 1.2[/tex]
a. Find the standard score associated with a gestation period of 13.8 months
This is Z when X = 13.8. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{13.8 - 15}{1.2}[/tex]
[tex]Z = -1[/tex]
The standard score associated with a gestation period of 13.8 months is of [tex]Z = -1[/tex]
b. Using the Empirical Rule and your answer to part a, what percentage of whale pregnancies will have a gestation period between 13.8 and 15 months?
The standard score associated with a gestation period of 13.8 months is of [tex]Z = -1[/tex], which means that it is one standard deviation below the mean.
The normal distribution is symmetric, which means that of the approximately 68% of measures within one standard deviation of the mean, 68%/2 = 34% are within one standard deviation below the mean(in this case, 13.8) and the mean(in this case 15), and 34% are within the mean and one standard deviation above the mean.
So 34% of whale pregnancies will have a gestation period between 13.8 and 15 months.
c. Would it be unusual for a whale to have a gestation period of 21 months? Why or why not?
Let's find the z-score
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{21 - 15}{1.2}[/tex]
[tex]Z = 5[/tex]
Since when [tex]X = 21[/tex], [tex]Z = 5 \geq 2[/tex], it would be unusual for a whale to have a gestation period of 21 months.
Mike did so well with his bike sale, he's going to Discount his helmets 15% off. If the Sale Price is $23.80, find the ORIGINAL PRICE of a helmet.
Answer:
$3.57
Step-by-step explanation:
Multiply $23.80 by %15
Change %15 to a decimal by multiplying it by 100.
0.15 x $23.80= $3.57
is the table linear or not
Answer:
No, the table is not linear.
Step-by-step explanation:
Between the x and y there has to be a constant rate. There is no constant rate.
A jar contains n nickels and d dimes. There is a total of 257 coins in the jar. The value of the coins is $17.35. How many nickels and how many dimes are in the jar?
Answer:
Here's what we know:
n + d = 20 (there are a total of 20 nickels and dimes)
.05n + .1d = 1.4 (total change equals $1.40)
There are a couple of ways to solve this. You can go the elimination method by multiplying the second equation by an amount to get rid of a variable, or we can go substitution by isolating a variable in the first equation. I'll go with elimination in this case:
-10(.05n + .1d = 1.4) this will cause the d-variable to equal 0:
n + d = 20
-.5n - d = -14
------------------
.5n = 6
n = 12
Now that we know n, we can solve for d:
12 + d = 20
d = 8
Check:
.05 * 12 + .1 + 8 = 1.4
.6 + .8 = 1.4
1.4 = 1.4
Step-by-step explanation:
The length of a rectangle is increasing at a rate of 9 cm/s and its width is increasing at a rate of 4 cm/s. When the length is 15 cm and the width is 12 cm, how fast is the area of the rectangle increasing
Answer:
The area of the rectangle is increasing at a rate of 168 square centimeters per second.
Step-by-step explanation:
Geometrically speaking, the area of a rectangle ([tex]A[/tex]), in square centimeters, is described by following expression:
[tex]A = w\cdot l[/tex] (1)
Where:
[tex]w[/tex] - Width, in centimeters.
[tex]h[/tex] - Height, in centimeters.
By Differential Calculus, we find an expression for the rate of change of the area of the rectangle ([tex]\dot A[/tex]), in square centimeters per second:
[tex]\dot A = \dot w\cdot l + w\cdot \dot l[/tex] (2)
Where:
[tex]\dot w[/tex] - Rate of change of the width of the rectangle, in centimeters per second.
[tex]\dot l[/tex] - Rate of change of the length of the rectangle, in centimeters per second.
If we know that [tex]w = 12\,cm[/tex], [tex]l = 15\,cm[/tex], [tex]\dot w = 4\,\frac{cm}{s}[/tex] and [tex]\dot l = 9\,\frac{cm}{s}[/tex], then the rate of change of the area of the rectangle is:
[tex]\dot A = \dot w\cdot l + w\cdot \dot l[/tex]
[tex]\dot A = 168\,\frac{cm^{2}}{s}[/tex]
The area of the rectangle is increasing at a rate of 168 square centimeters per second.
The television show 50 Minutes has been successful for many years. That show recently had a share of 15, which means, that among the TV sets in use, 15% were tuned to 50 Minutes. An advertiser wants to verify that 15% share value by conducting its own survey, and a pilot survey begins with 15 households have TV sets in use at the time of a 50 Minutes broadcast.
Required:
a. Find the probability that none of the households are tuned to Lindsay and Tobias. (Round to three decimal places as needed)
b. Find the probability that at least one household is tuned to Lindsay and Tobias.
c. Find the probability that at most one household is tuned to Lindsay and Tobias.
d. If a most one household is tuned to Linday and Tobias, does it appear that the 15% share value is wrong? Why or wh not?
Answer- b
Step-by-step explanation:
its b
What is missing in the percent what is number 45 of 80
Answer:
35
Step-by-step explanation:
Suppose that a committee is studying whether there is waste of time in our judicial system. It is interested in the mean amount of time individuals waste at the courthouse waiting to be called for jury duty. The committee randomly surveyed 81 people who recently served as jurors. The sample mean wait time was eight hours with a sample standard deviation of four hours. Construct a 95% confidence interval for the population mean time wasted. Which distribution should you use for this problem
Answer:
The t-distribution is used, as we have the standard deviation of the sample.
The 95% confidence interval for the population mean time wasted is between 7.12 hours and 8.88 hours.
Step-by-step explanation:
We have the standard deviation for the sample, which meas that the t-distribution should be 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 = 81 - 1 = 80
95% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 80 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.95}{2} = 0.975[/tex]. So we have T = 1.99
The margin of error is:
[tex]M = T\frac{s}{\sqrt{n}} = 1.99\frac{4}{\sqrt{81}} = 0.88[/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 8 - 0.88 = 7.12 hours.
The upper end of the interval is the sample mean added to M. So it is 8 + 0.88 = 8.88 hours.
The 95% confidence interval for the population mean time wasted is between 7.12 hours and 8.88 hours.
Consider △BTW as pictured below.
Find W.
Answer:
m<W: 23
Step-by-step explanation:
8x - 9 + 30x - 4 + 13x - 11 = 180
51x - 24 = 180
51x = 204
x = 4
m<W:
8x - 9
8(4) - 9
32 - 9
23
Matteo has &400 in his saving account. on average he spends $10 per week on buying apps. Luca has $200 in his savings account. he is saving $15 a week in order to buy a new Playstation. When will matteo and luca have the same amount of money?
Answer:
8 weeks
Step-by-step explanation:
Given data
Matteo
Amount= $400
Spending per week= $10
Hence his balance after x weeks is given as
y=400-10x-------------1
Luca
Amount= $200
Spending per week= $15
Hence his balance after x weeks is given as
y=200+15x-------------2
Equate 1 and 2
400-10x=200+15x
collect like terms
400-200=15x+10x
200=25x
x= 200/25
x= 8 weeks
Hence it will take 8 weeks
In a tennis tournament, 25% of Sarah’s serves were aces. Design a simulation to predict how many aces you expect Sarah to serve out of 50 serves.
HELP PLEASE I'LL GIVE BRAINLIEST!!!!!!!!!
Answer:
12.5
Step-by-step explanation:
u put the decimal at the end of 25 then u times it by 50 and there u get ur answer
hope this helps :D
Find two equivalent fractions
3/2
Answer:
4/6 8/12
Step-by-step explanation:
Can some body help me?
Answer:
24
Step-by-step explanation:
2(54-6x)=73-7x
108-12x=73-7x
108-73=-7x+12x
35=5x
x=7
UW=73-7x=73-7(7) = 73-49 = 24
Need Help ASAP
Thanks so much in advance...
Answer:
I will post 4,5 and 6 separately.
Find the volumes of the solids generated by revolving the regions bounded by the graphs of the equations about the given lines.
y = root x
y = 0
x = 3
the x-axis
the y-axis
the line x = 3
the line x = 6
Answer:
x-axis = [tex]\frac{9\pi }{2}[/tex]
y-axis = [tex]\frac{4\pi }{5} .3(^{\frac{5}{2} } )[/tex]
Line x =3 : [tex]\frac{44\sqrt{3} }{5} \pi[/tex]
Line x = 6 : [tex]\frac{84\sqrt{3}\pi }{5}[/tex]
Step-by-step explanation:
Given lines : y = √x
y = 0
x = 3
To determine the volumes generated we will use the disk method for each of the lines,
attached below is the detailed solution for line x =3 , same procedure will be repeated for each value of x and y to obtain the given results
The volume generated ( x axis )
= [tex]\frac{9\pi }{2}[/tex]
volume generated ( y _axis )
= [tex]\frac{4\pi }{5} .3(^{\frac{5}{2} } )[/tex]
Volume about x = 3
= [tex]\frac{44\sqrt{3}\pi }{5}[/tex]
Volume about x = 6
= [tex]\frac{84\sqrt{3}\pi }{5}[/tex]
A cube has an edge length of 12 meters. What is its volume, in cubic meters?
meters
3
Answer:
1728
Step-by-step explanation:
if its a cube then all sides are the same length. you need to times to base width and height. so it will be 12 times 12 times 12 which is 1728.
X/23 = 21/34 round to hundredths place
Answer:
The answer is 14.19
Step-by-step explanation:
34 / 23 = 1.48
21 / 1.48 = 14.19
I hope this helps you! :D
A 90 ounce bag of nuts has cashews and peanuts in it. The peanuts weight is 10 more than 3
times the weight of the cashews. Find the weight of the cashews and peanuts.
Answer:
20 ounces of cashews and 70 ounces of peanuts
Step-by-step explanation:
x+3x+10=90
4x+10=90
4x=80
x=20
10 points!!!!!!! Plssssss helpppppp
please i will give you brainly -1,8÷9 I need step by step
Answer:
-0.2
I couldn't get step by step but hope this answer helps out a little...
(Do you need it for ur assignment?)
Step-by-step explanation:
-18/9 = 2, 9 goes into 18, 2 times, but a negative divided by a positive always = a negative number so the answer would come out to be -2.
-18/9 = 2, 9 goes into 18, 2 times, but a negative divided by a positive always = a negative number so the answer would come out to be -2.
however is you were typing -1.8 / 9 then it would be -0.2. Multiplying -0.2 * 9 would give you -1.8. Same rule applies as to why it's negative
I wasn't sure if the comma was a typo in your question but I Hope this helps :)
Please Help i give brainies
Step-by-step explanation:
[tex] \sqrt{3} is \: between \: 1.73and1.74[/tex]
Which number produces a rational number when added to 1/5
Answer: 2/3
Step-by-step explanation:
Answer: -2/3
Step-by-step explanation:
Hope This Help?
Please Mark Me brainly!
Just look at the pic for the question
Answer: C
Step-by-step explanation:
NEED MAJOR HELP PLEASE
Answer:
∠ BDC = 30°
Step-by-step explanation:
The angle on the circle is half the measure of the central angle subtended by the arc BC
∠ BDC = [tex]\frac{1}{2}[/tex] × 60° = 30°
Johnny had 600 red apples and 400 blue oranges, then his friend gave him 20 red bananas. He eats all of the bananas, throws away 200 of the blue oranges because he couldn't finish them all, and he fed 100 of the red oranges to his pet rock. How many pumpkin pies does he have now?
Answer choices:
8,000,000
No, he has 6000 bananas
I think he just ordered some offline
He has 300 red apples
Answer:
4 im not sure
Step-by-step explanation:
What is radiant energy from the sun called
Answer:
Solar rays
Step-by-step explanation:
Either that or uv rays
Answer:
Electromagnetic Radiation
Step-by-step explanation:
What is 5+5? Please help the lol
Answer:
10
Step-by-step explanation:
5+5=10
your answer is 10
Answer:
10
Step-by-step explanation:
1+1= 2
1+1 = 2
2+2= 4
4 + 1 = 5
5 + 5 = 10
thank you to whoever helps
(3,1) would be the right answer
Need help on this question
Answer:
Step-by-step explanation:
arc between cars = 360°/25 = 14.4°
θ = 14.4° × π/180 ≅ 0.2512 radian
r = 150/2 = 75 ft
s = rθ = 75×0.2512 = 18.84 ft
area of circle = πr² = 75²π ≅ 17,662.5 ft²
area of sector = 17,662.5/25 = 706.5 ft²
What expression is equal to 5,007.992?
