# Posts by Jen

Total # Posts: 3,517

**statistics**

we are interested in testing at level of significance alpha =10 whether the population mean is different than 15. a random sample of size 25 is taken with a mean of 13.9. assume standard deviation is 2 and normally distributed population. find the values for zcrit

**statistics**

Assume that body temperatures of healthy adults are normally distributed with a mean of 98.2 degrees F and a standard deviation of .62 degrees F. suppose we take a sample of eight healthy adults. what is the probability that their mean body temperature will be greater than 98.4

**statistics**

Assume that body temperatures of healthy adults are normally distributed with a mean of 98.2 degrees F and a standard deviation of .62 degrees F. suppose we take a sample of eight healthy adults. what is the probability that their mean body temperature will be greater than 98.4

**pre-algebra**

We need more info. What is the full problem?

**geometry**

(1)r y-axis °r x-axis (2)T 2,-3 °y=x (3)r y=-x °D 3 (4)R o °R o HELP!!

**geometry**

Which composition would produce an image triangle whose area is not equal to the area of the original triangle?

**math**

Suppose that fifteen observations are chosen at random from the pdf f_Y(y) = 3y^2, 0<=y<=1. Let X denote the number that lie in the interval (1/2, 1). Find E(X). E(X) is the expected value or average.

**finance**

I am thinking that the answer is c because if the company is operating above its breakeven point and the fixed costs are constant then the profits should increase by more than 15% since they aren't receiving any additional costs.

**finance**

If a company has fixed costs and is operating above the breakeven point, when sales increase by 15%, profits will: a. increase by less than 15% b. increase by 15% c. increase by more than 15% d. decrease by less than 15%

**math**

two integers have sum of 23 and a difference of 7. which of the following is also true about these integers? A they have a product of 161. B they have a qoutient 4. C they have a product of 120. D they have a qoutient of 2.

**american history**

Yo chill anonymous :(

**physics**

A .1kg mass is located on the line between a 5kg mass and a 10kg mass. It is 4m to the right of the 5kg mass and 6m go the left of the 10kg mass. What is the magnitude and direction of the net force on the .1kg mass?

**math**

an amount invested in an account that offers 5% interest which is compounded annually. how long will it take for this amount to double?

**physics**

a helicopter has a speed relative to the air of 76km/h northeast. The speed of the wind relative to the ground is 28km/h south. 2 hours after leaving the ground, what is the displacement of the helicopter relative to the ground?

**math**

a) 7.49 miles b) 0.12 miles per minute

**Biology**

How can you experimentally determine the total volume of blood in a human?

**Science**

Are you then suggesting that because humans are not predators, their eyes have a more constricted view than owls?

**Science**

Why are your ears at the side of your head and not in front where your eyes are?

**chemistry**

sample of argon gas collected at a pressure of 1.11 atm and a temperature of 28.0 oC is found to occupy a volume of 20.3 liters. How many moles of Ar gas are in the sample?

**Physics**

A rock thrown with an initial velocity of 35 m/s at an angle of 48° with respect to the horizontal has a range of 963 m on a certain planet. What is the acceleration of gravity on this planet?

**MATH**

Assume that the population of heights of male college students is approximately normally distributed with mean of 72.83 inches and standard deviation of 6.86 inches. A random sample of 93 heights is obtained. Show all work. (A) Find the mean and standard error of the x ...

**MATH...PLZ HELP**

The width of the Confidence Interval is inversely related to the Maximum Error of Estimate. T or F? Why or why not?

**MATH....**

Determine the level of the confidence given the confidence coefficient z(α/2) for the following situation: z(α/2) = 1.96

**MATH**

Given a binomial distribution with n = 21 and p = 0.76, would the normal distribution provide a reasonable approximation? Why or why not?

**Math**

pattern rule for 2,3, ___, 7, 11, 13, 17, ___

**physics**

thank you so much!!!

**physics**

thank you! From here how would I get this: Suppose the torque you found for the last part is being produced by a force applied at a point 0.15·m from the axis. If the direction of the force is perpendicular to a line from the axis to that point, what is the magnitude of...

**physics**

Consider a 8·kg rod with a length of 0.6·m and rotating about an axis passing through its center. (a) What is its rotational inertia? (B) Suppose the rod is rotating counterclockwise and speeding up with a rotational acceleration of 7·rad/s2. What is the ...

**math**

Consider a 8·kg rod with a length of 0.6·m and rotating about an axis passing through its center. (a) What is its rotational inertia?

**math**

Consider a 8·kg rod with a length of 0.6·m and rotating about an axis passing through its center. (a) What is its rotational inertia?

**Biology**

Can genetic mutations also occur within mitochondria and cause diseases? if yes, how common are these diseases?

**Chemistry**

Hydrogen sulfide is an impurity in natural gas that must be removed. One common removal method is called the Claus process, which relies on the reaction: 8 H2S(g) + 4 O2(g)--> S(l) + 8 H2O(g) Under optimal conditions the Claus process gives 98% yield of S8 from H2S. If you ...

**Chemistry**

Which of the following solutions is the most basic? (a) 0.6 M NH3, (b) 0.150 M KOH, (c) 0.100 M Ba(OH)2. Explain.

**MATH**

A set of 50 data values has a mean of 18 and a variance of 4. I. Find the standard score (z) for a data value = 20. II. Find the probability of a data value < 20.

**math**

nevermind got it :-)

**math**

A large truck with a mass of 6500·kg and going 20·m/s east collides with a car whose mass is 1100·kg and which is at rest. If the impulse exerted on the car by the truck is 12000·N·s east, find the impulse exerted by the car on the truck. ...

**math**

Thank you sooo much!!! I wasn't dividing by the right number! can you also explain how to find the impulse of this problem? A large truck with a mass of 6500·kg and going 20·m/s east collides with a car whose mass is 1100·kg and which is at rest. If ...

**MATH**

i'm not sure how that site relates to my question at all???

**MATH**

Find the z-score for the standard normal distribution where: Area = 0.95 to the left of z

**MATH**

What percentage of the area of the standard normal distribution is between z = -1.00 and z = +1.00? How do you know this?

**Did i do this right??? STATS**

3. In testing a new drug, researchers found that 10% of all patients using it will have a mild side effect. A random sample of 14 patients using the drug is selected. Find the probability that: (A) exactly two will have this mild side effect (B) at least three will have this ...

**Math**

In testing a new drug, researchers found that 10% of all patients using it will have a mild side effect. A random sample of 14 patients using the drug is selected. Find the probability that: (A) exactly two will have this mild side effect (B) at least three will have this mild...

**math**

block A: mass = 100·g, spring stretched 10·cm block B: mass = 400·g, spring stretched 20·cm block C: mass = 200·g, spring stretched 20·cm block D: mass = 200·g, spring stretched 20·cm Rank the blocks, from largest to ...

**chemistry**

write a balanced equation for photosynthesis. express the answer as a chemical equation. identify all of the phases in the answer. during photosynthesis, plants use energy from sunlight to form glucose (C6H12O6(s)) and oxygen from carbon dioxide and water

**chemistry**

honestly all we do is labs during class i would love to take notes

**chemistry**

we dnt take notes that's why im so lost

**chemistry**

use standard enthalpies of formation to calculate delta Hrxn for the following reaction. 2H2S(g)+3O2(g)-->2H2O(l)+2SO2(g) express the answer using four significant figures Delta Hrxn = ? kJ

**chemistry**

use standard enthalpies of formation to calculate delta Hrxn for the following reaction. 2H2S(g)+3O2(g)-->2H2O(l)+2SO2(g) express the answer using four significant figures Delta Hrxn = ? kJ

**Stats....PLZ HELP....**

A bag of colored blocks contains the following assortment of colors: red (18), blue (14), orange (20), purple (14), green (10), and yellow (4). Construct the probability distribution for x.

**Stats**

Find the mean and standard deviation of the following probability distribution: x 1 2 3 P(x) 0.3 0.5 0.2

**Stats**

x y 1 -10.0 2 -20.0 3 -30.0 4 -40.0 5 -50.0 - What would be the slope of this regression line? - Would the correlation between x and y be positive or negative? - How would you interpret these data in terms of linear regression?

**Stats**

In testing a new drug, researchers found that 10% of all patients using it will have a mild side effect. A random sample of 14 patients using the drug is selected. Find the probability that: (A) exactly two will have this mild side effect (B) at least three will have this mild...

**math**

Consider the experiment of simultaneously tossing a fair coin and rolling a fair die. Let X denote the number of heads showing on the coin and Y the number of spots showing on the die. a. List the outcomes in S. b. Find Fx,y(1,2). Part a is easy. It's part b that I don'...

**eth**

should united states government policy favor certain kinds of immigrants?

**statistics**

Seventy million pounds of trout are grown in the U.S. every year. Farm-raised trout contain an average of 32 grams of fat per pound, with a standard deviation of 7.5 grams of fat per pound. A random sample of 34 farm-raised trout is selected. The mean fat content for the ...

**statistics**

Seventy million pounds of trout are grown in the U.S. every year. Farm-raised trout contain an average of 32 grams of fat per pound, with a standard deviation of 7.5 grams of fat per pound. A random sample of 34 farm-raised trout is selected. The mean fat content for the ...

**Chemistry**

n=4,n=6

**Math**

You are given the following data. # of Absences Final Grade 0 96 1 92 2 71 3 66 4 60 5 51 A. Find the correlation coefficient for the data. B. Find the equation for the regression line for the data, and predict the final grade of a student who misses 3.5 days.

**Math**

Three cards are selected, one at a time from a standard deck of 52 cards. Let x represent the number of tens drawn in a set of 3 cards. (A) If this experiment is completed without replacement, explain why x is not a binomial random variable. (B) If this experiment is completed...

**Math**

A. If the correlation coefficient is 0.65, what is the sign of the slope of the regression line? B. As the correlation coefficient decreases from -0.97 to -0.99, do the points of the scatter plot move toward the regression line, or away from it?

**Math**

This is so confusing to me :( what would i do next??

**Math**

For the table that follows, answer the following questions: x y 1 1/2 2 1 3 3/2 4 - Would the correlation between x and y in the table above be positive or negative? - Find the missing value of y in the table. - How would the values of this table be interpreted in terms of ...

**Can somehelp me with this ASAP plz?!?!?! Stats**

For a particular sample of 63 scores on a psychology exam, the following results were obtained. First quartile = 57 Third quartile = 87 Standard deviation = 9 Range = 51 Mean = 72 Median = 72 Mode = 98 Midrange = 57 I. What score was earned by more students than any other ...

**Stats**

In each of the four examples listed below, one of the given variables is independent (x) and one of the given variables is dependent (y). Indicate in each case which variable is independent and which variable is dependent. I. Rainfall; Crop yield II. Taxi fare; Length of ride ...

**Stats**

For a particular sample of 63 scores on a psychology exam, the following results were obtained. First quartile = 57 Third quartile = 87 Standard deviation = 9 Range = 51 Mean = 72 Median = 72 Mode = 98 Midrange = 57 I. What score was earned by more students than any other ...

**Stats....how do i do this??**

It doesn't show .16, it shows .15 as p-value of 0.4404 and z as 1.15....what do i do??

**Stats....how do i do this??**

SAT I scores around the nation tend to have a mean scale score around 500, a standard deviation of about 100 points, and are approximately normally distributed. What SAT I score within the population would have a percentile rank of approximately 16? Im not sure how to do this...

**Stats...is this correct??**

Scores on the Stanford-Binet Intelligence scale have a mean of 100 and a standard deviation of 16, and are presumed to be normally distributed. A person who scores 68 on this scale has what percentile rank within the population? z = (68-100)/16 z = -32/16 = -2 So would it be ...

**Stats...is this correct?**

Yay!! Thank u!!

**Stats...is this correct?**

A sample of purchases at the local convenience store has resulted in the following sample data, where x = the number of items purchased per customer and f = the number of customers. x 1 2 3 4 5 f 5 15 8 8 7 1. What does the 15 stand for in the above table? 2. Find the midrange...

**Stats**

I. Dependent variable; Independent variable II. Independent variable; Independent variable III. Independent variable; Dependent variable IV. Dependent variable; Dependent variable Sorry I misread it. Is this correct?

**Stats**

6. In each of the four examples listed below, one of the given variables is independent (x) and one of the given variables is dependent (y). Indicate in each case which variable is independent and which variable is dependent. I. Rainfall; Crop yield II. Taxi fare; Length of ...

**Stats**

For a particular sample of 63 scores on a psychology exam, the following results were obtained. First quartile = 57 Third quartile = 87 Standard deviation = 9 Range = 51 Mean = 72 Median = 72 Mode = 98 Midrange = 57 I. What score was earned by more students than any other ...

**CHEMISTRY HELP**

1) The specific heat of solid copper is 0.385 J/g(C). What thermal energy change occurs when the temperature of a 34.10 g sample of copper is cooled from 35.7 degrees Celsius to 13.9 degrees Celsius? Answer: -286.3 J This amount of heat is used to melt solid ice at 0.0 degrees...

**Statistics**

SAT I scores around the nation tend to have a mean scale score around 500, a standard deviation of about 100 points, and are approximately normally distributed. What SAT I score within the population would have a percentile rank of approximately 16?

**Statistics**

It says to calculate using this: Nk/100 So im not sure if i did it correctly....

**Statistics**

z = (68-100)/16 z = -32/16 = -2 So would it be 95%?

**Statistics**

Scores on the Stanford-Binet Intelligence scale have a mean of 100 and a standard deviation of 16, and are presumed to be normally distributed. A person who scores 68 on this scale has what percentile rank within the population?

**Statistics**

So the midrange of items purchases would be 3. 5+30+24+32+35 = 126 items were purchased by the customers in this sample. Did i do this correctly?

**Statistics**

A sample of purchases at the local convenience store has resulted in the following sample data, where x = the number of items purchased per customer and f = the number of customers. x 1 2 3 4 5 f 5 15 8 8 7 •What does the 15 stand for in the above table? •Find the ...

**Statistics**

I. dependent variable II. independent variable III. independent variable IV. dependent variable Is this correct?

**Statistics**

In each of the four examples listed below, one of the given variables is independent (x) and one of the given variables is dependent (y). Indicate in each case which variable is independent and which variable is dependent. I. Rainfall; Crop yield II. Taxi fare; Length of ride ...

**Statistics**

A student scored 81 percent on a test, and was in the 77th percentile. Explain these two numbers.

**Statistics**

In terms of the mean and standard deviation: -What does it mean to say that a particular value of x has a standard score of +2.1? -What does it mean to say that a particular value of x has a z-score of -2.4?

**Stats**

For a particular sample of 63 scores on a psychology exam, the following results were obtained. First quartile = 57 Third quartile = 87 Standard deviation = 9 Range = 51 Mean = 72 Median = 72 Mode = 98 Midrange = 57 Answer each of the following: I. What score was earned by ...

**math**

A 1200·kg elevator is attached to a cable whose tension is 11900·N. What is the magnitude of the elevator's acceleration? ____ m/s

**chemistry**

what is the typical relationship between the rate of reaction and the value of the equilibrium constant? A) it is a direct porportionality B) it is an exponential proportionality C) it is an inverse proportionality D) there is no relationship between these factors

**math**

A ball is thrown from the edge of a cliff with an initial velocity of 60·m/s upward. Answer the following questions using + (upward) and - (downward) to indicate the direction of the velocity. Ignore air resistance and assume the ball does not hit the ground during the ...

**physics**

The hang-time of a basketball player who jumps a vertical distance of 2 feet (0.61 m) is about 0.70 second. What will be the hang-time if the player reaches the same height while jumping 3 feet (0.91 m) horizontally?

**Stats**

A set of 50 data values has a mean of 15 and a variance of 25. Find the standard score of a data value = 20. I'm not sure how to do this....please help

**Help plz!! Math....**

Start with x = 100 and add four x values to make a sample of five data such that the standard deviation of these data equals 0

**Help plz!! Math....**

A set of 50 data values has a mean of 15 and a variance of 25. Find the standard score of a data value = 20

**Physics**

A 4.3-kg block slides down an inclined plane that makes an angle of 26° with the horizontal. Starting from rest, the block slides a distance of 2.1 m in 5.1 s. Find the coefficient of kinetic friction between the block and plane.

**sentence**

I show my appreciation to my parents for all they do for me :)

**4th grade math**

add all of them and divide by how many sets there are which is 5.... 92 + 96 + 99 + 103 + 88 = 478/5 = 95.6

**Statistics**

Start with x = 100 and add four x values to make a sample of five data such that the standard deviation of these data equals 0

**Statistics**

A set of 50 data values has a mean of 15 and a variance of 25. Find the standard score of a data value = 20

**Can someone help me please? MATH**

hmmmmm i guess it is....thank u :)

**Can someone help me please? MATH**

Identify the sampling technique used to obtain this sample: Each person boarding a plane is asked to flip a coin; those showing “tails” have their luggage searched.

**Math**

interesting....thank you for your example, it definitely helped me :)