Sunday
December 11, 2016

# Posts by Gray

Total # Posts: 74

Differential Calculus
A water trough is 10 m long and a cross section has the shape of an isosceles trapezoid that is 30 cm wide at the bottom, 80 cm wide at the top, and has height 50 cm. If trough is being filled with water at the rate of 0.2 m^3/min how fast is the water level rising when the ...
September 5, 2016

Differential Calculus
A norman window has the shape of a rectangle surmounted by a semicircle. If the perimeter of the window 10 m, express the area A of the window as the function of width x of the window.
June 28, 2016

Solid Mensuration
A metal hollow bar whose cross-section and dimensions are shown below weighs 8x10^3 kg/m^3 and measures 2m in lenght. Determine the mass of the metal bar with a square hole section.
March 31, 2016

Depreciation: A construction company purchases a bulldozer for \$160,000. Each year the value of the buldozer depreciates by 20% of its value in the preceeding year. Let V sub n be the value of the bulldozer.(Let n=1 be the year the bulldozer purchase.) a.) Find the Formula. b...
March 6, 2016

Algebra
Depreciation: The purchase value of an office computer is \$12500. Its annual depreciation is &1875. Find the value of computer after 6 years. Aritmetic Sequence
March 6, 2016

Algebra
Salary Increases: A man gets a job of \$30000 a year. He promised \$2300 raise each subsequent year. Find his total earnings for a 10-year period.
March 3, 2016

salary increases: A man gets a job with a salary of \$30000 a year. He is promised a \$2300 raise each subsequent year. Find the total earnings for a 10 year period. Arithmetic Sequence,:
March 2, 2016

Math
2X/2=288/21 X=44 ,Linear equation. :)
January 20, 2016

A handful of 65 coins consist of pennies, nickels and dimes. The number of nickels is 4 less than twice of pennies, and there are 13 more dimes than nickels. How many coins of each kind are there? Solve using Gauss-Jordan Elimination.
January 19, 2016

chemistry
Ethanol glycol has a density of 1.11 g/cm^3. What is the volume in L of 4.1 kg of this liquid?
August 31, 2014

chemistry
How do you convert 3.345 kJ to mJ?
August 31, 2014

chemistry
How would you convert 77 degrees F to kelvins? Can you explain it please because I don't really understand how to get it to Fahrenheit.
August 30, 2014

math
Simplify (3x-2)^3 - (4x+5)^2
August 27, 2014

Chemistry 1 HN
Find the mass of iron heated to 85 degrees celcius that was added to 54.0 grams of water. The temperature of the water changed from 20 degrees celcius to 60 degrees celcius. The specific heat of the iron is 0.045 J/g degrees celcius
January 1, 2013

health care
identify a contemporary health care issue and write a paper that describe the impacts from a business organization
June 18, 2011

math and music
Thanks. I already know all of what you said, except for that last sentence (Wouldn't that only apply in certain keys? C seems much easier for 3rds, 4ths, and 5ths than C#). I just want to know how to generate that list in a spreadsheet.
December 4, 2010

math and music
How would you go about listing all of the integer ratios? I would like to have the integers listed in ascending order by the product of each integer's numerator and the denominator. This is because in music, more "complex" ratios sound more dissonant. Every list ...
December 4, 2010

maths
(8)*8-64/(8)+4 parentheses 8*8-64/8+4 no exponents 64-8+4 multiplication & division 60 addition & subtraction pemdas = p, e, m&d, a&s
December 4, 2010

Math
2^x = (3/2)^6 solve for x
November 29, 2010

Composition and Communication
Adverbs are words that modify adjectives, verbs, or other adverbs. Many end in -ly. Check out the Wikipedia article for examples.
November 26, 2010

Algebra 1
The formula for slope is change in y/change in x. F(x) is the same as y in this case. Change in y = 2--2 = 4. Change in x = -3-5 = -8. 4/-8 = -1/2
November 26, 2010

Math
((4x^3)(y^-2))/((2x^-1)(y^4) The way you typed your equation leaves some ambiguity; I'm assuming this is it. First move the variables with negative exponents to opposite sides of the fraction bar, and make those exponents positive. Then add the exponents and multiply the ...
November 20, 2010

collegeMath
This looks more like late middle school math to me. Anyway, the equation is f(4) = 8(4^2) = 8(16) = 128. Notice I replaced x with 4 to set up the equation, so that it reads "f of 4 (the force needed to stretch 4 centimeters) equals 8 times 4 to the power of two"
November 19, 2010

Chemistry
Oh, sorry, I thought I got to your question earlier than I did. I guess this site doesn't work too well for real time discussions...
November 19, 2010

Chemistry
Find the molar mass of N2H2. Now find the number of moles that are in 5.0 x 10^14g of N2H2. With me so far?
November 19, 2010

math and music
How would you go about listing all of the integer ratios? I would like to have the integers listed in ascending order by the product of each integer's numerator and the denominator. This is because in music, more "complex" ratios sound more dissonant. Every list ...
November 19, 2010

geometry
It helps a lot to draw a picture. Although the problem does not specify how the points are arranged, I assume they are in a line. Your picture should be a line with points a, b, and c on the line. Now write 3x above the ab segment and 5x above the bc segment. Draw one of those...
November 19, 2010

bioweb .wku .edu/courses/biol225/225lab9 .html gsu .edu/~bioasx/closeopen .html According to the first article, they don't have circulatory systems at all, and I assume that's because they do not have a heart. Remove the spaces to access the webpages.
November 19, 2010

math
the carat symbol ^ means "to the power of"
November 16, 2010

math
Before you start multiplying, you need to make sure everything is in the same units. For length, you can use either cm or m. I'll pick meters. That means we have to convert 100cm to m. There are 100 cm in a m, so 100cm = 1m. Meters x meters = square meters (m^2), and 1m x ...
November 16, 2010

history
take the space out of the URL
November 16, 2010

history
I wasn't able to find a "reeducation movement", but searching the web and library for the history of Native American education should provide some good sites. Here is a short overview: nrcprograms . org/site/PageServer?pagename=aief_hist_main
November 16, 2010

recreational math, music
How would you go about listing all of the integer ratios, preferably in a spreadsheet? I would like to have them listed in ascending order by the product of the numerator and the denominator, because in music, more "complex" ratios produce more dissonance. One list ...
November 16, 2010

math 12
It helps to start with a simpler problem. Try solving it manually, by drawing out each possible seating arrangement, with three members instead of six. The problem specifies a circular table, so we can probably assume that there is a difference between circular and linear ...
November 16, 2010

math
a+(a+1)+(a+2)=(a+2)x2 combine like terms 3a+3=2a+4 subtract 2a from both sides a+3=4 subtract 3 from both sides a=1 the integers are 1,2,3
November 16, 2010

math
this site should explain everything (remove spaces) purplemath . com/modules/orderops . htm
November 8, 2010

Chemistry
Hydrogen peroxide is H2O2. First, convert the given amount (1kg O2) into moles. One mole of O2 is 2x16g = 32g. 1kg = 1000g. 1000/32 = 31.25, so we need 31.25 moles of O2. One mole of H2O2 contains one mole of O2, so we need 31.25 moles of H2O2 to produce 31.25 moles of O2. The...
November 8, 2010

Alg & Trig 2
Find the least common denominator by multiplying the prime factors, 7 and 2, and x to get 14x. Multiply each fraction by 7x, 2, and 14 respectively so that they share the denominator 14x. Add the numerators to get (7x+74)/14x. Simplify 7x/14x to 1/2 and 74/14x to 37/7x to get...
November 5, 2010

Algebra
The decaf coffee contains 3 units of caffeine per cup (100 minus 97). The regular coffee contains 100 units of caffeine per cup. Two cups of regular coffee contains 200 units, so you would have to drink 200/3 = 66.666 cups of decaf. 66.666*8 = 533.333 ounces
November 2, 2010

Biology
The Wikipedia article "Cell cycle" has an excellent diagram in the Phases section.
October 28, 2010

Chemistry
convert .25 L into mL by multiplying by 1000, then divide the volume of ethanol by the volume of water
October 28, 2010

spanish
B looks good to me -- wordreference dot com is excellent for looking up conjugations, especially if you install the Firefox shortcuts
October 28, 2010

Pre-Calculus Algebra
The book could be wrong. The wording is a little confusing too.
October 24, 2010

Pre-Calculus Algebra
It helps to draw a picture. You can ignore the length of the fence, add 2 to 8 to get the length of the one leg of the triangle (the other is 13), and use the formula a^2 + b^2 = c^2
October 24, 2010

Mathematics for Liberal Arts
(4/52)*(3/52)*(2/52)*(1/52)
October 24, 2010

math
this looks like a good explanation studyzone . org/mtestprep/math8/a/primefactors7l . cfm
October 24, 2010

Spanish
Got it, thanks! By the way, when you're talking/writing, how do you decide where to put the "se" since it doesn't matter where it goes?
October 20, 2010

Spanish
¿Cómo se dice "I am going to bed." en español? ¿Puede se dice "Me acuesto"?
October 20, 2010

engish language art
Could you rephrase the question?
October 20, 2010

math
2/3 * 12 = 24/3 = 8
October 20, 2010

elementary-math
That sounds pretty advanced for an elementary class. One way you could start to solve this is to use a few different values for n and see what you get. Using n=1,2,3 we get p=7,13,19. Do that for a bunch of numbers (a spreadsheet program like Excel or Openoffice Calc will help...
October 20, 2010

Chemistry
I am looking for a systematic way to balance chemical equations, instead of doing them by hand. Can someone help me understand the table in the How Does It Work? section at tinyurl dot com/28mngtt
September 27, 2010

vocab
I've always hated problems like that. You can use this site, just set the maximum number of words to one. wordsmith dot org/anagram/advanced dot html
September 23, 2010

Chemistry
Thanks. I read ahead a few pages and found what I wanted to know.
September 23, 2010

Chemistry
Why do H and F form a covalent bond, while Na and Cl form an ionic bond?
September 23, 2010

Math
The weighted mean of the numbers 204, 206, 207, and 208 is 207.2. How could I arrive at the weight (or possible weights) of the four numbers?
September 23, 2010

Are you supposed to fill in the diagram? It's just a matter of organizing and using every bit of information the problem gives you. Try to work backwards from this answer to learn how to do it. none-22, tng-73, ds9-17, voy-11, tng/voy-31, tng/ds9-23, ds9/voy-14, tng/ds9/voy-9
September 22, 2010

Jiskha
How does one become a tutor?
September 22, 2010

Jiskha
Who is "we"?
September 22, 2010

Jiskha
Why were some of my answers deleted? I'm not mad, I just want to know how this site works.
September 22, 2010

Jiska
I wonder who benefits from the adverts, then...
September 22, 2010

Jiska
So are most of the question-answerers on this site volunteers, or are they paid by the advertising?
September 22, 2010

Math
2:3, "two to three", and 2/3 all mean the same thing
September 22, 2010

Math
Divide 20/35 and 24/36, and pick the answer equal to 2/3.
September 22, 2010

Chemistry
But if the question wanted me to find the moles of O, how would it be phrased? Thanks
September 21, 2010

Chemistry
"How many moles of oxygen are required to react completely with 5 mol C(8)H(18)?" 2C(8)H(18) + 25O(2) => 16CO(2) + 18 H(2)O In the question, how do I know if "oxygen" means the molecule O(2) or the element O?
September 21, 2010

Calc
Y-intercept represents the maximum number of spaces he can rent, renting each space for \$0. X-intercept represents the maximum amount he can charge per space, renting 0 spaces. Also a minor correction to slope: The more he charges, the fewer spaces he will rent.
September 21, 2010

statistics
n a local university,40% of the students live in the dormitories. A random sample of 80 students is selected for a particular study. What is the probability that the sample proportion (the proportion living in the dormitories) is between 0.30 and 0.50?
November 11, 2009

Physics lab
During a lab, we dropped a ball from the second story of our school and found out the distance, ave. time, ave. velocity, final velocity and the acceleration. One of the questions is: If we could redo this experiment from a 300 ft radio tower instead of from the second story ...
September 22, 2008

Find the velocity (in m/s) of a free-falling object released from rest after it has fallen 100m. I don't understand the formulas to use or anything. please help.
September 16, 2008