# Posts by jim

Total # Posts: 1,662

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.

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.

math
Right!

MATH
Yes!

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.

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...

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 ...

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

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

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...

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 ...

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 ...

algebra
-x / 8 = 3 Multiply across by 8: -x = 3 * 8 Multiply across by -1: x = 3 * 8

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 ...

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,....

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.

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

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.

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

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?

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

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...

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

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

science
Is there a question?

math
Subtract 2x from both sides.

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.

MATH 116
The question didn't paste.

-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!)

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 ...

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 ?

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.

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

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!

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?

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.

math

Math
commutative

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

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 ...

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)

Gr. 12 Data Management
Wikipedia. List_of_poker_hands

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.

Gr. 12 Data Management
This one's a lot easier. :-)

Gr. 12 Data Management
Sorry, so it is.

Gr. 12 Data Management

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)

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 ...

Math
You're welcome.

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. :-)

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 ...

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-...

math
Maybe.

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

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 ...

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

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 ...

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 ...

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.

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...

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 ...

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...

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 ...

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 ...

algebra
You're welcome, Rachel.

algebra
All correct!

There isn't a question here.

Math

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.

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.

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.

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.

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

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

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 ...

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

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 ...

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 ...

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&#...

Math
You're welcome!

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 ...

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 ...

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. ...

Math
No, the sale price of the house doesn't matter. It could be 6,000 or 6,000,000; we don't care for this purpose. What we know is that for every 6 dollars Stephen borrows, he has to pay 7 back. What we don't know, that we would like to know, is how long Stephen has ...

Math
Interest is usually shown as a percentage rate per year, but since we don't know the number of years, we can't calculate it here. Mortgages are usually for 10-30 years. If it was one year, which would be very very short for a mortgage, the rate would be 1/6, since he ...

Math
I presume that by mortgage here is meant to total value to be paid back for the loan. When the bank lends you money, you have to pay back more than you borrowed, the extra being the interest. We don't know how much Stephen borrowed, but we know he has to pay back 7/6 of ...

Math
The reason you didn't think of that is just that you haven't had enough practice yet. :-) Keep plugging at it, and you'll be doing these things without even having to think about them!

Math
Good question! Really good question, since you're thinking of the more general case. You can't use the same trick there; I'm afraid you'll have to calculate. The standard way, that will always work, is to find a common denominator of the two fractions, so that ...

Math

Math
Right! If it's bigger than one, the number on top is larger. Now, is 19/6 greater or less than one? Is 4/27 greater or less than one? So without calculating anything, you can show that the two fractions cannot be equal.

Math
I like this question! It's simple, but should make you think, and there are many ways to approach it. I'd hate to deprive you of the thinking experience, but here are some questions for you. What does it mean for a statement about numbers being equal to be "true&...

Science
Search for "population ecology" and "population biology". You might find what you're looking for there. I think "population ecologist" may be the term you're looking for.

science

science
1800g = 1.8kg How many 1.8 kg are in 80 kg?

math (algebra)
Take the next one then. Step by step. 9x = 5y + 3 Parallel, but going through (-2, 4). x is -2. y is 4. It must be 9x = 5y + something 9*-2 = 5*4 + something. What is the something?

math (algebra)
That's OK. First you solve it. Then you put it into the form you need. Point slope form just means moving y to the left hand side, and everything else to the right. Consider: x + 5y = 47 Subtract x from both sides: 5y = 47 -x Divide by 5 y = 47/5 - x/5

math (algebra) -oops
I typoed, and it might confuse you. Sorry. 5*8 is 40, or course, not 47. x + 5y = something 7 + 5 * 8 = something 7 + 40 = something = 47 So a line parallel to x+5y=2, containing (7,8) is x+5y=47.

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