Bryant

The mean amount spent by a family on food per month is $500 with a standard deviation of $75. Assuming that the food costs are normally distributed, what is the probability that a family spends more than $410 per month? Plesase show formula and calcuation...

15 years ago

A resort tracks the number of days each guest stays. They've discovered that this variable is normally distributed with a mean of 9 days and a standard deviation of 3. They would expect 10% of the guest stay longer than how many days? Please show statisti...

15 years ago

A bank wishes to estimate the mean balances owed by their MasterCard customers within $75. The population standard deviation is estimated to be $300. If a 98% confidence interval is used, how many cardholders should be sample. Please provide sample size f...

15 years ago

Construct a descriptive statistics for 100 employees using intervals of 0-4, 4-8, 8-12, 12-16, 16-20.

15 years ago

Formula used to easily calcuate sample size. Please give example.

15 years ago

Formula used to calculate confidence interval..please give example. Thanks

15 years ago

How can I calcualate the probability of a normal distribution. Please present formula and an example. Thanks.

15 years ago

Using the Substitution method solve 7x+5y=-23 -6x+y=25

15 years ago

Can someone please help me complete these calculations for my lab; I am having some trouble. A. Standardization of Na2S2O3 -Mass of KIO3 in 100mL = 0.09600g -Calculate Molarity of KIO3= ? Please check: 0.09600g/(214.0g/mol)=4.486x 10^-4 mol -4.486 mol/0.1...

14 years ago

Hi DrBob, Sorry about that, I wasn't very clear! Can someone please help me complete these calculations for my lab; I am having some trouble. A. Standardization of Na2S2O3 -Mass of KIO3 in 100mL = 0.09600g -Calculate Molarity of KIO3= ? Please check: 0.09...

14 years ago

lim (x^3-1)/(x^3+2x^2y+xy^2-x^2-2xy-y^2) (x,y)->(1,0) my question is can you approach (1,0) with y=x and does that change the the limit to lim f(x,x) (x,x)->(1,1) in which case i get 3/4 as the limit. and if this is not how i go about doing it can you poi...

13 years ago

lim (x^3-1)/(x^3+2x^2y+xy^2-x^2-2xy-y^2) (x,y)->(1,0) alright i approached this at y=0. and got the limit as 3. where else can i approach this from to see if the limit really exist which im hoping it doesn't. i tried y=x-1 and that was a mess and i also t...

13 years ago

If u = log(r), where r^2 = (x-a)^2 + (y-b)^2, and (x-1) and (y-b) are not zero simultaneously, show that d^2u/dx^2 + d^2u/dy^2 = 0. I first used some of the properties of log and made u = 1/2 * log((x-a)^2 + (y-b)^2) Then made u = 1/2 * ln((x-a)^2 + (y-b)...

13 years ago

Let z = ∫(e^sin(t)dt) from x to y a = x b = y I tried thinking about it like a chain rule but even then i'm a little unsure. I know dz/dt = e^sin(t). Can you please point me in the right direction if i'm supposed to use the chain rule.

13 years ago

Suppose R is the rectangle 1<=x<=4, |y|<=2 and evaluate the double integral ∫R∫f(x,y)dA, where f(x,y)= y/(1+3x^4)^(1/2). I first decided to integrate with respect to y first (which I think I can choose to do) I am a little confused at this part though cau...

13 years ago

Consider ∫R∫syDA, where R is the square R=[0,1]x[0,1]. Let us compute some Riemann sums. For any positive integer n we partition R into n^2 little squares Rij each with sides 1/n long. Within each little square we evaluate the integradn at the point (x*ij...

13 years ago

Find the volume V of the solid in the rst octant bounded by y = 0, z = 0, y = 3, z = x, and z + x = 4. The best part about this problem is that I solved it using basic geometry but am expected to do it using a triple integral that will take up a whole pag...

13 years ago

A 160-lb man carries a 25-lb can of paint up a helical staircase that encircles a silo witha radius of 20 ft. If the silo is 90 ft high and the man makes exactly three complete revolutions, how much work is done by the man against gravity in climbing to t...

13 years ago

x dy/dx + y = 1/y^2, solve using bernoulli's equation. i got to du/dx + (2u)/x = 2x(u)^(-1/2). the u^(-1/2) is obviously a problem if im going to solve it using an integrating factor. if that is not what you yourself have gotten to then please show me my...

13 years ago

(x^4-11x^3+43x^2-40x+19) ÷ (x^2-9)

12 years ago

(x^4-11x^3+43x^2-40x+19) ÷ (x^2-9) Long division

12 years ago

After Khalil gave Benjamin 3/5 of the rocks in his collection, Benjamin had 70 rocks. If Benjamin had 25 rocks in the beginning, how many rocks did Khalil have in the beginning?

11 years ago

You are offered $12,000 for an annuity at 3.9% compounded monthly for 6 yrs what would the monthly payments be?

9 years ago

In 1995-96 academic year there were 86,087 bachelor degrees awarded. That number fell to 71,261 for 2002-2003 school year. In 2008-09 it rose to 120,488 . How much greater was the percent increase from 2003 to 2009? How much was the percent decrease from...

9 years ago

I am confused how you would get an order pair from that....can you help?

15 years ago

im guessing you meant sin(x)^5. in which case yeah you did it wrong. you derive (x)^k , k being a constant, like this k*(x)^(k-1)*x' so f'(x)=5sin(x)^4*cos(x)

13 years ago

alright thanks, my teacher never showed us that if you set one of the variables equal to zero you can make it a one variable function. so say i approach x=0 and find the limit of that to be infinity. does the original function f(x,y) not exist?

13 years ago

or does x=0 not work because x does not equal zero on the point (1,0). cause my teacher was fairly lazy in class and used the point (0,0) for every example.

13 years ago

then what can i approach by as well cause i also tried y=x-1 and that was just a mess.

13 years ago

cos(sin(x))*cos(x) 16sin^3(x)*cos(x) d/dx(f(x))= f'(x)*x'

13 years ago

solve for what?

13 years ago

use google-fu next time and look these things up. volume of a rectangular prism = abc just convert inches to feet. then multiply.

13 years ago

oh never mind. i looked back and saw that i differentiated wrong on a step

13 years ago

i meant ∫R∫xydA

13 years ago

never mind. i thought about it and it is the work done by gravity. not the man. which leads me to another question. how exactly would you find the work done by the man. would he be represented as another vector or or in the vector field?

13 years ago

oh, never mind. I've seen my mistake. disregard this question.

13 years ago

Calculate the return on investment in dollars and as a percentage for an investment that you purchase for $500 and sell for $600.

12 years ago

4 1/2

12 years ago

1.5 liter flask is filled with nitrogen at pressure of 12 atmosphere. What size would be required to hold this gas at a pressure of 2.0 atmosphere?

9 years ago