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March 29, 2015

Posts by jim


Total # Posts: 1,474

math
Whatever number it is has to divide evenly both by 12 and by 8. For example, could it be 80? Well, that would use up exactly 10 packages of 8 buns, but would it use up exactly some number of packages of hot dogs? So it can't be 80. And similarly, it can't be 50, or 81...
October 20, 2009

Math
Take it a bit at a time. Write 3(r^2+2p-p^3) so that there are no brackets. Now write -(6r^2+p^3-p) so there are no brackets. Now add both together, bringing together the r^2, p and p^3 terms.
October 20, 2009

Math
I'm sorry, but I'm still not clear. Maybe it's ((30/5) *( 3-2)) /(2-2/3)) ? That would be (6 * 1) / (4/3) = 6 * 3 / 4 = 4.5
October 20, 2009

Math
You 'll have to clarify that. Do you mean: 30 / (5*3-2)/ (2-2/3) ?
October 20, 2009

Math
All right!
October 20, 2009

calculus
This and the other seem to be similar. Best to talk about the general method. 1. Find an expression for the distance between the two at time t. In this case, with Pythagoras' help, that's sqrt( (25t+30)^2 + (16t)^2) = sqrt(881t^2 + 1500t + 900) Nasty-looking thing. ...
October 20, 2009

Math
It depends on the person! And how fast they jog, and even what terrain they're jogging over. Jogging might burn 300-500 calories an hour, so anything from 1000 to 1750 in a week.
October 20, 2009

Math
Do you need extra brackets? Should that be f(x,y)=xy/(x^2+y^2) because without the brackets, the assertion is false.
October 20, 2009

Math
12-|-13+15| = 12 - 2 = 10 Right.
October 20, 2009

Math
14. I don't get the same answer. a) Get size of property = 188 * 100 = 18800 b) Get size of lake = pi * 36^2 = 4069.44 c) Get size of island = pi * 12^2 = 452.16 d) Covered in water = (b) - (c) Percentage = (d) / (a) 15. I don't get exactly this answer either, but very...
October 20, 2009

Math
Yes. 6. Yes. 8. Yes. 9. Yes. 11. Yes!
October 20, 2009

physics
Correct!
October 20, 2009

Algerbra1
One. You can tell without calculating because the slopes are different.
October 20, 2009

math
1. Yes. 2. Yes 3. Yes 4. Yes!
October 20, 2009

math
1. Correct 2. Correct 3. Close. Associative property. 4. Correct 5. Correct 6: Nope, assumng I'm reading the question right: 7/8 - 9/3 7. Correct 8. Correct 9. 41 and 43 are twin primes 10 Correctamundo. 9.
October 20, 2009

Math
You go to a cafe with your two friends. You are treating them, and you are all having milk and a cinnamon bagel. That is one such situation. How is the order of operations important? Work out the bill.
October 20, 2009

math
Right!
October 20, 2009

MATH
Yes!
October 20, 2009

Math
Start with 612. Does it divide by 2? Yes. So write it as 306*2 Does it divide by two again? Yes. So write it as 153*2^2 No more 2s. Try 3. Keep going until you can find no more factors.
October 20, 2009

Math
In logic, "or" means _either one_ of them is true. Maybe one is true, maybe the other, maybe both, but as long as at least one of the statements is true, then the whole statement is true. Given that, cal you see which statements are true? We define "prime number...
October 20, 2009

Math
I think the answer expected is "exact", but for a different reason. (Unless somebody went missing, or the food was contaminated!) An estimate is going to be high, and you know it will be high: 20 * 40. A closer estimate 20 * 40 - 40 will be low, but close, and what ...
October 20, 2009

physics
Pythagoras OK, but remember you have to square all the sides. 12.5^2= x^2 + 7.2^2 156.25 = x^2 + 51.84
October 20, 2009

math
It's just a line between and including the points -4 and 10.
October 20, 2009

Calculus
I'm not quite sure about the question, but I'll guess. The MVT is about the average slope. The average slope is the slope of the sstraight line between (1, 5) and (4,5), which is zero. I'm guessing you're looking for the point or points in the curve whose slope...
October 20, 2009

Math 350..help!
Don't let all the digits and decimals throw you off. The number of years after 1980 just means that in 1981, t = 1, and 1982, t = 2, and so on. You need to differentiate 0.07t^3 - 3.1t^2 + 54.3t - 230 Which, really, is just differentiating t^3, t^2, and t and multiplying ...
October 20, 2009

Probability
I don't think you've given us all the information from the table. Maybe you haven't recognised all of the information. Does "50% of them" means "50% of all employees" or "50% of males"? That makes the question ambiguous, and offhand I ...
October 20, 2009

algebra
-x / 8 = 3 Multiply across by 8: -x = 3 * 8 Multiply across by -1: x = 3 * 8
October 20, 2009

maths
1) is what I get too. 2. a) I agree with 69 as well. 63 digits will get you to p36. Another 66 digits will get you another 33 pages. b) When I calculate this, I get 204 digits for 104 pages: 9 digits for 1-9 180 digits for 10-99 15 digits for 100-104 I think you're ...
October 20, 2009

Maths
Mark is right, but for numbers of the form x0x, you can of course use any digit, not just zero, so 101 also implies 111, 121, 131,....
October 19, 2009

Algebra 2 URGENT
The problem as you have expressed it is: 1/u^2 - 2u -1/u^2 - 4 = (1/u^2 -1/u^2) - 2u - 4 = -2u -4 I suspect that maybe there are brackets missng, maybe 1/(u^2-2u) -1/(u^2-4) ? or maybe not, or maybe different, like 1/u^2 - (2u-1)/(u^2-4) ? but I can't tell.
October 19, 2009

Algebra 2 URGENT
In this, like the first one, just gather your similar terms together and write what's left.
October 19, 2009

Algebra 2 URGENT
This one doesn't get much simpler. You might consider that 1/16t^2 is simpler than 1/(4t)^2, or you might not.
October 19, 2009

Algebra 2 URGENT
Hm. If the question was 1/(y^2-y-2)+1/(y^2+y) then I would get the same answer you give, but that is very different from 1/y^2-y-2+1/y^2+y
October 19, 2009

Algebra 2 URGENT
That is all the work. There's a -y and a +y; they cancel out. There are two 1/y^2 terms; they add. There's a -2. That's it. Unless there are brackets you've omitted in the question?
October 19, 2009

Algebra 2 URGENT
1. Gather your ys together and your 1/y^2 terms together: 1/y^2-y-2+1/y^2+y = 0y+2/y^2-2 = 2/y^2-2
October 19, 2009

Math
"The number 18 is multiplied by a number called "r"". How would you write that? Hint: If x was multiplied by 7, you would write it as 7x. "When 6 is subtracted from" How would you indicate that 6 is subtracted from a number? For example, how would...
October 19, 2009

science
Sorry, answering other questions. I haven't come across the terms before in this context, so I'm afraid I can't help.
October 19, 2009

science
OK, but what is the question you need help with?
October 19, 2009

science
Is there a question?
October 19, 2009

math
Subtract 2x from both sides.
October 19, 2009

8th grade
Answered below
October 19, 2009

Math
This is very like, but different than, Olivia's equation below. Gather your constants together. 15n -5 -20 - 12 = 13 15n -37 = 13 Now add 37 to both sides and then divide by 15.
October 19, 2009

MATH 116
The question didn't paste.
October 19, 2009

8th grade
-5(-3n+4)-12=13 Add 12 to both sides: -5(-3n+4)=25 Divide across by 5: 3n - 4 = 5 Add 4 to both sides: (you fill this in) Finally, divide across by 3: (you fill this in too!)
October 19, 2009

MATH 116
Let's first consider why $10,000=$6,000-n is wrong. It only has an equal sign, and if we subtract 6000 from both sides, we get n=4000, which is definitely not right; n could be 6001, or 10000, or 6789. We need two inequality signs to express this. What do we know? n is ...
October 19, 2009

Algebra
3.8y-4.7=3.8y+17.5 is just not true for any y. Subtract 3.8 y from both sides. Is -4.7 = 17.5 ?
October 19, 2009

ALGEBRA 1
If r is >= 8, then it is not true. (|3-8| = 5) If r is <= -2, then it is not true, (|3-(-2)| = 5) So r is a member of the interval ]-2, 8[, carefully not including either -2 or 8 themselves.
October 19, 2009

math algebra 1
Let n be the number of nickels d the number of dimes n = 4d because we are told "4 times as many nickels as dimes" The total value is: n * 5 + d * 10 = 600 Divide across by 5: n + 2d = 120 and n=4d, so 4d + 2d = 120 6d = 120 d= 20 So n = 4d = 80
October 19, 2009

algebra
First, get all the constants on one side, so 1. subtract 2 from both sides. Now you have a multiple of 7 on the left. You only want a single y on the left so: 2. Divide both sides by 7. Now you have a nice clean inequality in y!
October 19, 2009

MATH
If Greg is G years old, then how old is twice Greg's age? And Michael (M) is one year more than that. Does that help?
October 19, 2009

MATH!
What do you have to multiply 1/4 by to get to 1? 4 1/2 x - 1/4 y = 7/2 Multiply across by 4: 2x - y = 14 y = 2x -14 Now multiply the second one across by 3 to finish it yourself.
October 19, 2009

math
Answered above
October 19, 2009

Math
commutative
October 19, 2009

algebra
You can also do them with the formula (y-y1)/(y2-y1) = (x-x1)/(x2-x1) So: (y+1)/(5/2+1) = (x+1/2)/(3+1/2) y+1 = x+1/2 y = x - 1/2 and (y+3) /(9+3) = (x-6)/(-1-6) (y+3) / 12 = (x-6) / -7 -7y -21 = 12 x -72 y = -12x/7 +51/7
October 19, 2009

math
Ms. Sue has the right idea! I was trying to explain this in a big long answer, but wasn't getting anywhere useful. Actually, I think this question is phrased confusingly. I think it should say "use x to represent _the number of houses with_ floor plan #1 and y to ...
October 19, 2009

statistic
Find a Percentile to Z-Score Calculator. You can Google one, and likely there's a table of this in your text. That'll tell you how many SD below the mean you have to go. I make it about -1.28 standard deviations, so that'll be about 34,000 - (1.28 * 2000)
October 19, 2009

Gr. 12 Data Management
Wikipedia. List_of_poker_hands
October 18, 2009

Gr. 12 Data Management
OK. I owe you an answer for that mistake, so try 13C4 * (4C1)^3 * 4C2 * 4 which also accords with Wikipedia's answer.
October 18, 2009

Gr. 12 Data Management
This one's a lot easier. :-)
October 18, 2009

Gr. 12 Data Management
Sorry, so it is.
October 18, 2009

Gr. 12 Data Management
Answered below.
October 18, 2009

Math
Ah. I see. I was reading it differently. (x^2-5x-24) (x-3) --------- * ------ (x^2-6x+9) (x-8) = ((x-8)(x+3)(x-3))/((x-3)(x-3)(x-8)) x-8 and x-3 cancel top and bottom, and leave you with: (x+3)/(x-3)
October 18, 2009

Math
x^2-5x-24 = (x-8)(x+3) x^2-6x+9 = (x-3)(x-3) Make sure you understand these two first! Factoting x^2 + ax + b, you look for two numbers that ADD to a, but MULTIPLY to b. So in the first case, 6*4 = 24, but they don't add to 5, no matter where I put the minus. But -8 * 3 ...
October 18, 2009

Math
You're welcome.
October 18, 2009

Math
Yes! When you get confused because there are just too many letters and numbers, try to isolate them and look at one at a time. The secret of success is getting used to being confused. :-)
October 18, 2009

Math
Your answer is absolutely right, but just not yet simplified. You should see that you can divide by 3 top and bottom. That reduces the constants to 121 and 33. Now look at the x and q terms without the constants: x^3q^6 ------ xq^3 Can you divide top and bottom by x? By q? By ...
October 18, 2009

Math
1. is correct, but not completed: (21+22)/98w (careful to use the brackets) =43/98w 2. I went wrong on this one myself, by taking the question down wrong, but I have it straight now. Divide 6b/(9b-27) top and bottom by 3. You can do that without changing its value. So 6b/(9b-...
October 18, 2009

math
Maybe.
October 18, 2009

Math
Um, no. Wrong turn somewhere. It's a LOT simpler than that. Your numerator will be : (1-sinx)(1+sinx) - cos^2x
October 18, 2009

Math
Do you mean solve it or prove it? It is an identity, so there really isn't a specific solution: it's true for all x. I suggest you try reformatting as (1-sin x)/cos x - cos x/(1+sin x) = 0 Then bring both fractions to the common denominator (cosx)(1+sinx), and I think ...
October 18, 2009

fin 200
When the yield curve is upward sloping, generally a financial manager should: A. utilize long-term financing B. lease C. utilize short-term financing D. wait for future financing
October 18, 2009

writing
Googling, I am guessing that this is from "The Adventures Of Ulysses" by Evslin, and that that book mostly extracts stories from The Odyssey. I don't know Evslin, but given the Odyssey as a source, I can guess at the characterisation. He sailed in a ship to ...
October 18, 2009

Financing
Look up the definitions of "quick ratio" and "current ratio". What is the difference? The major difference in most companies will be the size of inventory as a current asset. The quick ratio will always be smaller than the current ratio. From that, you can ...
October 18, 2009

Financing
quick ratio that is much smaller than the current ratio reflects A. a small portion of current assets is in inventory. B. that the firm will have a high inventory turnover. C. that the firm will have a high return on assets. D. a large portion of current assets is in inventory.
October 18, 2009

algebra
It was just too easy for you! That happens quite a lot. To everyone, especially me. :-) I look at a problem and think "I don't get it", and 10 minutes later when I'm thinking about something else, I get the "DOH!". Me and Homer Simpson. And now you...
October 18, 2009

algebra
Oh, come ON! This one's a no-brainer. You could do it in your sleep, if you're the same rachel who posted earlier today :-) Draw the axes. Draw the point (2,4). Draw a horizontal (across) line through it. What value of y does every point on that line have? So the ...
October 18, 2009

Gr. 12 Data Management
I'm not sure how this is data management. Anyway, I found this one longer and trickier than I first thought it would be. Calculating the number of hands without pairs is easy: You can choose from 52 for your first card. That rules out that card and the three others of same...
October 18, 2009

finance
LIFO = Last In First Out. Whatever you just bought, or made, is what you sell next. If I start with 5 units @$10, then buy 7 @$20, then sell 10, which 10 do I sell? I sell the _last_ 10 that I got, which will be the 7@$20 and 3 of the 5 @$10. That will leave me with the first ...
October 18, 2009

algebra
You have a start point 4 miles from the origin, when this story begins. You then walk at a rate of speed for a specified time. There really isn't much equationing (which isn't a word!) to be done here, since you know your speed and time: Distance from start point = 4 ...
October 18, 2009

algebra
You're welcome, Rachel.
October 18, 2009

algebra
All correct!
October 18, 2009

Math Help Please
answered below, at length
October 17, 2009

9th grade
There isn't a question here.
October 17, 2009

Math
answered below
October 17, 2009

Math-Triangles
Sara, I understand what you're doing, but I think the question wasn't put clearly. Neither of the triangles here is right-angled. The two triangles are similar: their sides have the same ratio. We know one is 2*7:3*7:4*7 and the other is 2*9:3*9:x and we need to find x.
October 17, 2009

Math-Triangles
I answered this below, but you didn't specify that the triangles are similar in the original question. That means that the clue is in my original answer.
October 17, 2009

MATH
Noting that ACK is not the same as KAC, You can choose from 5 letters for your first Then you can choose from 4 letters for your second. Finally you can choose from 3 letters for your first So you can choose in 5 * 4 * 3 ways.
October 17, 2009

9th grade (math)
answered below, for "kevin"
October 17, 2009

physic
OK, now I see the whole question. No, your number is right but you need to check your direction. Take two steps east, 2 steps north, 2 steps south. You are now two steps ____ of where you started.
October 17, 2009

physic
If your question was: "julianna walked 45 meters WEST, 45 meters south , and 45 meters north" then you are correct!
October 17, 2009

Math
Yes, absolutely! Try this: 18 : 27 : x = 2*9 : 3*9 : x 14 : 21 : 28 = 2*7 : 3*7 : 4*7 Clearer now?
October 17, 2009

Math
I don't understand the question. You have only one missing length for two triangles? I do note that the ratio of sides in the two cases is 2:3:(1/3)x 2:3:4 Just considering triangle 1, x could be anything less than 45 (bonus question: why?). Maybe you want x so that the ...
October 17, 2009

Math
Only back for a few minutes. Then I have to go help a grown-up whose "homework" is even harder than yours. :-)
October 17, 2009

Math
Suppose the price today is 100. In one year, that'll be 106, which is 100 * 1.06. The next year, it'll be 6% up again, which is 106 * 1.06 = 112.36 The next year after that, it'll be 6% up again, which is (106 * 1.06) * 1.06 = 112.36 * 1.06 = 119.10. You seeing a ...
October 17, 2009

math
The best way to do question 1 is to draw a graph of each. Draw your x, y axes, then find two points on each of the lines, then use a ruler to draw the line that they're both on. Which two points? Any two will do, but it's easier to draw if they're not too close ...
October 17, 2009

operating system
I only have time for a short answer at the moment. You need to sort by the PPID parent process ID first, so that you can trace each process back through its parents. Everything traces back to 0 eventually. Example: Process 6017's parent is 6003. 6003's parent is 1. 1&#...
October 17, 2009

Math
You're welcome!
October 17, 2009

Math
Let's estimate the problem first. Handy to check our thinking. There are 3 tiles per foot, right? And there are a bit over 10 feet to tile, at 3 tiles per foot, so our answer is going to be near 30 tiles. If you multiplied 1/3 by 10, you'd get about 3 as an answer, so ...
October 17, 2009

Math
(Yes I did, but I'm back. Hey, it's Saturday!) Yes! Not that the _current_ average is .2857, just that the average of the new games that are added on is .2857. If Harry batted exactly .308 in the next 28, his average would stay the same, at .308. If he bats lower, the ...
October 17, 2009

Math
Forget his current average for a minute. Now, what batting average does 8 hits in 28 make? (Divide 8 by 28.) We don't know how that .308 was made up, but we know that if 8/28 is greater than .308, he's batting better than his past average, so the average will go up. ...
October 17, 2009

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