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oldie (m)
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Some of these problems have mathematical solutions, but not practical solutions! Like this one: Rasheed can mow his mother's lawn in 6 minutes. His brother Peter can mow it in 9 minutes. How long will it take them to do it together, if each has his own lawnmower. The answer depends on many variables Are the mowers clones of each other? Same efficiency? The time that will be used by the two brothers can never be determined in practice Dem fit quarrel self and the job is never done  So always remember prototypes are always different from the real thing But I like the zeal put in by contributors |
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donchichi
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ok, if I'm to go with that I'll have 0.5(6+x) + 1.25x = 12.75 1.75x=9.75 x=5.57, I don't know doesn't look like a good answer, maybe the analogy i'm using is all wrong then @kobe whats the answer, I can't think of any other way to solve it  exactly 4Him If you use this equation you don't get a round figure. He can't have mowed the lawn 5.6 times.
Guys, i agree that u'll not get an integer for an answer, but i didnt set the question . i also tried multiplying by 6 but just looking at the question and statement in particular, you should actually add 6 to it. But its all good. |
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kobe (m)
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Rasheed can mow his mother's lawn in 6 minutes. His brother Peter can mow it in 9 minutes. How long will it take them to do it together, if each has his own lawnmower.
t(rasheed) = 6 minutes
t(peter) = 9 minutes
Rasheed mows one lawn over 6 minutes
Peter mows one lawn over 9 minutes
Rate of work for Rasheed = L/6
Rate of work for Peter = L/9
Now we want to mow one lawn when both are doing it together.
Time it takes to mow one lawn
amount of work done = rate at which the work is done multiplied by the time they worked.
So we want time.
1L= (L/6 + L/9)t
t = L/(L/6+L/9) = 54/15mins
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LearnBook
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Dele shares out 15 sweets. He gives Ifeoma 1 for every 4 he eats. How many does Ifeoma get?
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donchichi
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Dele shares out 15 sweets. He gives Ifeoma 1 for every 4 he eats. How many does Ifeoma get?
15? |
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oldie (m)
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Dele shares out 15 sweets. He gives Ifeoma 1 for every 4 he eats. How many does Ifeoma get?
Should it not be 3? 4x + x = 15 5x = 15 x = 3 Correct me if I am wrong |
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PL+C
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I can't see the ladies contributing anything here, if na Romance thread now, they will tell you how Solomon slept with over 1000 women closing his eyes, kissing them and doing legs like lizard. The only two ladies that tried to show face only applauded the guys but no contributions from them. Whether the guys are working jargons they don't know.  |
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donchichi
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Should it not be 3?
4x + x = 15
5x = 15
x = 3
Correct me if I am wrong
The question already said He shares out 15 sweets and the only recipient mentioned is ifeoma. So ifeoma gets all 15 sweets that was shared. If the question was rephrased as " Dele has 15 sweets", then the answer would be 3. |
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oldie (m)
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@ donchichi
Thanks!
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RichyBlacK (m)
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A die is cast five times, what is the probability of getting at least a six?
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LearnBook
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donchichi: shares out is the right phrase. It's more like 4 for Dele, 1 for Ifeoma. Dele is sharing but that does not exclude him from the process.
Anyway, enough of the semantics here. Yes, the correct answer is 3. Dele gets 12, Ifeoma gets 3 and the ratio 12:3 is equivalent to 4:1.
Have a good day.
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bawomolo (m)
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A die is cast five times, what is the probability of getting at least a six? (1/6)*5=5/6 |
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GeeCee (m)
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I bow my head for the mathematicians in the house. A very big WELL DONE 2 u.
But wait, where are the ladies?
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Olumide7 (m)
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Integrate: xlnx
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kobe (m)
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integral of xlnx using int by parts = uv-integral (vdu)
u = lnx dv = x
du = 1/xdx
v = integral of dv = x2/2
applying formula.
uv = x2/2lnx
integral vdu = integral (x2/2 * 1/x dx) = x/2
integral xlnx = x2/2lnx - 1/4x2 + C
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4Him (m)
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integration was the main reason i withdrew from advanced maths class in high school.
Too confusing.
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spikedcylinder (f)
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Reading through this thread, all i can think to say is, Una dey craze, |
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Imani (f)
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I can't see the ladies contributing anything here, if na Romance thread now, they will tell you how Solomon slept with over 1000 women closing his eyes, kissing them and doing legs like lizard. The only two ladies that tried to show face only applauded the guys but no contributions from them. Whether the guys are working jargons they don't know. Mr bigmouth PLC, how dare you claim the ladies are "olodo"  . Of course Romance topics are more interesting. Anyway, i have to admit, since this thread started, i have been trying to dust off all the "cobwebs" from my brain . I did do A level Maths but that was like 8 years ago now. But no excuses, i will try to rise to some of the simplier chalenges  donchichi: shares out is the right phrase. It's more like 4 for Dele, 1 for Ifeoma. Dele is sharing but that does not exclude him from the process.
Anyway, enough of the semantics here. Yes, the correct answer is 3. Dele gets 12, Ifeoma gets 3 and the ratio 12:3 is equivalent to 4:1.
Yes 15.
So, which one is it?. I initially agreed with Oldie, using 4:1 ratio, however, after seeing donchichi's working, I can see why he arrived at 15. What is missing is the key word, is it Dele "shared out" 15 sweets thereby excluding him from the process or "has" 15 sweets, which includes him? Either answer is correct, depending on whether Dele is included or not. |
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Imani (f)
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1. Expand (4+2x)6 in ascending powers of X up to the power of X3
2. Solve the following quadratic equations 3x2 + 5x -8 =0
3. X2 + 2X -8 =0
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huxley
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What is the product of:
(x-a)(x-b)(x-c)(x-d) . . . . (x-z)
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Damest09 (f)
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wow, this is good. I wonder what kind of job u people r doing with this level of brain u posses and how much money make by it.
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Damest09 (f)
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Well done anyway
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donchichi
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1. Expand (4+2x)6 in ascending powers of X up to the power of X3
2. Solve the following quadratic equations 3x2 + 5x -8 =0
3. X2 + 2X -8 =0
1. Can be solved using some theorem i can't remember 2. (3x+8)(x-1) = 0 ; x = 1, x = -8/3 3. (x-2)(x+4) = 0; x = 2, x = -4 |
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kobe (m)
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I don't understand what you mean by in powers of X up to 3, but
Expansion of (2X+4)6 using the binomial theorem is:
Coefficients are : 1 6 15 20 15 6 1
1(2x)640+6(2x)541+15(2x)442+20(2x)343+15(2x)244+6(2x)145+1(2x)046
Simplifies to:
64x6+768x5+3840x4+10240x3+15360x2+12288x+4096
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Imani (f)
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1. Expand (4+2x)6 in ascending powers of X up to the power of X3
2. Solve the following quadratic equations 3x2 + 5x -8 =0
3. X2 + 2X -8 =0
1. Use binomial theorem. To find the answer subsititute 4 for a and 2x for b: 4 6 + ( 6 C 1)(4 5)(2x) + ( 6C 2)(4 4)(2x) 2 + ( 6 C 3)(4 3)(2x) 34096 + (6 ×1024 ×2x) + (15 ×256 ×4x 2) + (20 ×64 ×8x 3) 4096 + 12288x + 15360x 2 + 10240x 3 2. Use the quadratic equation formulae 3. Solve by factorising the answers are in the below post
2. (3x+8)(x-1) = 0 ; x = 1, x = -8/3
3. (x-2)(x+4) = 0; x = 2, x = -4
Correct answers to numbers 2 and 3. welldone, i will post the workings later. |
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kobe (m)
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What is the product of:
(x-a)(x-b)(x-c)(x-d) . . . . (x-z)
Product of (x-a)(x-b)(x-c)(x-d) . . . . (x-z) = (x-a)(x-b)(x-c)(x-d) . . . (x-x), (x-z) = (x-a)(x-b)(x-c)(x-d) . . . .(0), . (x-z) =0*(x-a)(x-b)(x-c)(x-d) . . . . (x-z) = 0 |
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Imani (f)
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Product of (x-a)(x-b)(x-c)(x-d) . . . . (x-z)
= (x-a)(x-b)(x-c)(x-d) . . . (x-x), (x-z)
= (x-a)(x-b)(x-c)(x-d) . . . .(0), . (x-z)
=0*(x-a)(x-b)(x-c)(x-d) . . . . (x-z)
= 0
Kobe, you are good.   . I didnt get as far as (x-x). but your working is spot on and makes sense. And of course anything multipled by zero is zero. |
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kobe (m)
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good ke. all of you guys are just too good. even you sister imani, i'm amazed at your superpower.
I gotta post more problems.
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kobe (m)
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A boot that costs x dollars is marked down by 20 percent off its original price on Monday, then an additional 10 percent on Tuesday. What is the price of the jacket, in terms of x?
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kobe (m)
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Given x2 - y2 = 77 and x + y = 11 find x?
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