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March 29, 2024, 08:16:53 am

Author Topic: Mathematics Question Thread  (Read 1296908 times)  Share 

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RuiAce

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Re: Mathematics Question Thread
« Reply #1770 on: April 28, 2017, 08:00:53 pm »
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Can someone please help me with this question




mcheema

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Re: Mathematics Question Thread
« Reply #1771 on: April 28, 2017, 09:03:13 pm »
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Hopefully I didn't mess up whilst I had alcohol in my system

Thanks for your help . I realised my mistake, i mixed the signs up

asd987

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Re: Mathematics Question Thread
« Reply #1772 on: April 29, 2017, 12:26:14 am »
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Hi, why do the rates have to be in absolute values?

jamonwindeyer

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Re: Mathematics Question Thread
« Reply #1773 on: April 29, 2017, 12:39:15 am »
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Hi, why do the rates have to be in absolute values?

Hey! If you think about it, how could a positive rate of change ever be directly equal to a negative rate of change? They are opposite in sign by definition, meaning they can't be equal! Positive numbers can't equal negatives - If you try doing it without absolute values, you'll have no answer :) we just want when the magnitude of the rates of change is the same! :)

bananna

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Re: Mathematics Question Thread
« Reply #1774 on: April 29, 2017, 08:30:22 am »
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Hi!
can someone please list the formulas you need to know in series and sequences?
I was away for the first lesson and don't understand the layout of my textbook
thank you!

RuiAce

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Re: Mathematics Question Thread
« Reply #1775 on: April 29, 2017, 11:16:15 am »
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Hi!
can someone please list the formulas you need to know in series and sequences?
I was away for the first lesson and don't understand the layout of my textbook
thank you!
- General term of an AP
- Partial sum of an AP
- General term of a GP
- Partial sum of a GP
- Limiting sum of a GP

Formulas-wise that's it. Processes-wise there's more

jamonwindeyer

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Re: Mathematics Question Thread
« Reply #1776 on: April 29, 2017, 12:15:06 pm »
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Hi!
can someone please list the formulas you need to know in series and sequences?
I was away for the first lesson and don't understand the layout of my textbook
thank you!

And all of those are on your reference sheet! Bottom right of the first page ;D

anotherworld2b

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Re: Mathematics Question Thread
« Reply #1777 on: April 29, 2017, 03:53:28 pm »
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CanI have some help with this question please? I'm not sure where I went wrong

jamonwindeyer

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Re: Mathematics Question Thread
« Reply #1778 on: April 29, 2017, 05:22:18 pm »
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CanI have some help with this question please? I'm not sure where I went wrong

You've miscounted the double ups (the seven total is correct) ;D the total ways you can double up is two 1's, two 2's, two 3's, two 4's, two 5's or two 6's - That's six of the thirty six possible outcomes! So:


anotherworld2b

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Re: Mathematics Question Thread
« Reply #1779 on: April 30, 2017, 12:07:14 am »
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Thank you for help :)
I was also working on this question but I'm not sure what I did wrong again  :-\

You've miscounted the double ups (the seven total is correct) ;D the total ways you can double up is two 1's, two 2's, two 3's, two 4's, two 5's or two 6's - That's six of the thirty six possible outcomes! So:



RuiAce

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Re: Mathematics Question Thread
« Reply #1780 on: April 30, 2017, 12:09:51 am »
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Thank you for help :)
I was also working on this question but I'm not sure what I did wrong again  :-\

Not too sure why you put the probability in the denominator as well

anotherworld2b

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Re: Mathematics Question Thread
« Reply #1781 on: April 30, 2017, 01:07:48 am »
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I see what I did wrong now.
Thank you for your help
Not too sure why you put the probability in the denominator as well

anotherworld2b

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Re: Mathematics Question Thread
« Reply #1782 on: April 30, 2017, 01:00:26 pm »
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Im not sure how to do this question. Can i have help please?

jamonwindeyer

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Re: Mathematics Question Thread
« Reply #1783 on: April 30, 2017, 03:20:12 pm »
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Im not sure how to do this question. Can i have help please?

I don't think you've considered the totals in that table properly!! It should look like this:



So Part (a), for example, would be:



Part (b), you'd look at the total winning amounts progressively, and go, "Okay, do 40% of my possible outcomes sit above this value?" 40% of 25 outcomes is 10, so find the value with 10 outcomes above it! I don't think you'll get exactly 40, but get as close as possible :)

Edit: Woops, there is a value where \(P(x>??)=0.4\), find it! ;D

Part (c), find the average win (it will be less than $5), that gives you the average profit per game (\(5-\mu\)) and you can go from there ;D

Thebarman

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Re: Mathematics Question Thread
« Reply #1784 on: April 30, 2017, 09:21:17 pm »
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Hey guys, can someone help me with the following questions please? I keep getting 0 as the answer, and i'm not sure why.

1) Find the area bounded by the curve x=y^2-2y-3 and the y-axis

2) Find the area bounded by the curve x=-y^2-5y-6 and the y-axis
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