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March 29, 2024, 07:04:57 am

Author Topic: Mathematics Question Thread  (Read 1296876 times)  Share 

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katnisschung

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Re: Mathematics Question Thread
« Reply #885 on: November 10, 2016, 06:16:56 pm »
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Lucia currently earns $25,000
her wage increases by 5% each year.
Find
a) her wage after 6 years
b) her total earnings (before tax)
in 6 years
get me out of here

RuiAce

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Re: Mathematics Question Thread
« Reply #886 on: November 10, 2016, 06:21:14 pm »
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Lucia currently earns $25,000
her wage increases by 5% each year.
Find
a) her wage after 6 years
b) her total earnings (before tax)
in 6 years



Part b) is just weird. Although it looks to me like they meant the sum, their wording isn't clear. I'm not providing a solution to that one without knowing what's going on (so provide the answer if you want a solution)
« Last Edit: November 10, 2016, 06:24:59 pm by RuiAce »

jamonwindeyer

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Re: Mathematics Question Thread
« Reply #887 on: November 10, 2016, 06:26:25 pm »
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Lucia currently earns $25,000
her wage increases by 5% each year.
Find
a) her wage after 6 years
b) her total earnings (before tax)
in 6 years

I'll take a stab at what it means! This is a geometric series question, where \(a=25000\) and ](r=1.05\) (the 5% interest rate).

The wage after 6 years is just the 6th term (assuming the question means the sixth, like, the wage during the sixth year, which is why my answer differs from Rui's). The question makes a bit more sense this way.



Then the total earned is just the sum of the first six terms:



This topic is just about knowing your formula and knowing the numbers to sub :) hope this helps!
« Last Edit: November 10, 2016, 07:40:01 pm by jamonwindeyer »

katnisschung

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Re: Mathematics Question Thread
« Reply #888 on: November 10, 2016, 06:28:25 pm »
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thanks ruiace and jamon
also i think the answers are wrong
the common ratio of a geometric series is 4 and the sum of
the first 5 terms is 3069 find the first term
« Last Edit: November 10, 2016, 06:30:27 pm by katnisschung »
get me out of here

RuiAce

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Re: Mathematics Question Thread
« Reply #889 on: November 10, 2016, 06:31:08 pm »
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I'll take a stab at what it means! This is a geometric series question, where \(a=25000\) and ](r=1.05\) (the 5% interest rate).

The wage after 6 years is just the 6th term (assuming the question means the sixth, like, the wage during the sixth year, which is why my answer differs from Rui's). The question makes a bit more sense this way.



Then the total earned is just the sum of the first six terms:



This topic is just about knowing your formula and knowing the numbers to sub :) hope this helps!
Yeah the question was just irritating with its wording. Upsetting when you're studying business at uni haha

thanks Ruiace! it popped up in a series exercise?

also i think the answers are wrong
the common ratio of a geometric series is 4 and the sum of
the first 5 terms is 3069 find the first term
« Last Edit: November 10, 2016, 06:33:49 pm by RuiAce »

katnisschung

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Re: Mathematics Question Thread
« Reply #890 on: November 10, 2016, 06:41:03 pm »
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I'll take a stab at what it means! This is a geometric series question, where \(a=25000\) and ](r=1.05\) (the 5% interest rate).

The wage after 6 years is just the 6th term (assuming the question means the sixth, like, the wage during the sixth year, which is why my answer differs from Rui's). The question makes a bit more sense this way.



Then the total earned is just the sum of the first six terms:



This topic is just about knowing your formula and knowing the numbers to sub :) hope this helps!

question why did you use the arithmetic series formula?

a
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RuiAce

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Re: Mathematics Question Thread
« Reply #891 on: November 10, 2016, 06:41:43 pm »
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question why did you use the arithmetic series formula?

a
Haha lol I thought something was weird but I didn't pick up on it. I think he made a mistake there.

katnisschung

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Re: Mathematics Question Thread
« Reply #892 on: November 10, 2016, 06:47:36 pm »
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Haha lol I thought something was weird but I didn't pick up on it. I think he made a mistake there.

phew thats why there was a discrepancy between both your answers  ;D
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jamonwindeyer

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Re: Mathematics Question Thread
« Reply #893 on: November 10, 2016, 07:40:46 pm »
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phew thats why there was a discrepancy between both your answers  ;D

Sorry just fixed it up! Note also that Rui and I interpreted Part (a) differently, which could lead to different answers for (b) (it's a bad question) :P

katnisschung

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Re: Mathematics Question Thread
« Reply #894 on: November 10, 2016, 08:32:15 pm »
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should i write notes for my maths test
i know y'all did 3 or 4 unit and are maths geniuses
and jamon and jake advice against it
and i know the emphasis of solving problems over
writing notes but i personally find that writing notes
helps me to remember all aspects of the topic.

tips?
note i am not a maths genius i take 2u and get around 80s
(my teacher keeps on saying my results have fluctuated and
i have 'potential'  ;D let's hope so)

oh and when i mean writing notes i mean like transcribing
everytime after i have a maths lesson
« Last Edit: November 10, 2016, 08:35:25 pm by katnisschung »
get me out of here

RuiAce

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Re: Mathematics Question Thread
« Reply #895 on: November 10, 2016, 08:35:23 pm »
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should i write notes for my maths test
i know y'all did 3 or 4 unit and are maths geniuses
and jamon and jake advice against it
and i know the emphasis of solving problems over
writing notes but i personally find that writing notes
helps me to remember all aspects of the topic.

tips?
Back when there was no "reference sheet" I found it acceptable for some people to write a formula sheet or formula book. Things in there were meant to be really basic and serve no more purpose than be a refresher, and their only advantage was that they're going to be easier to use than textbooks.

The fact that the reference sheet has all the formulas you actually need really downs on this. I don't see any more that you can do than just printing it off and dropping in a few annotations here and there (A3 paper is fine for this though). I am with them in that in general doing "notes" for maths is not advisable, because it really doesn't help you remember as much as you think it would.

The furthest you should ever go with notes is about 5 dot points per topic, just highlighting some key areas of concern. If you ask me, that is.
« Last Edit: November 10, 2016, 08:37:33 pm by RuiAce »

jamonwindeyer

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Re: Mathematics Question Thread
« Reply #896 on: November 10, 2016, 09:01:00 pm »
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should i write notes for my maths test
i know y'all did 3 or 4 unit and are maths geniuses
and jamon and jake advice against it
and i know the emphasis of solving problems over
writing notes but i personally find that writing notes
helps me to remember all aspects of the topic.

tips?
note i am not a maths genius i take 2u and get around 80s
(my teacher keeps on saying my results have fluctuated and
i have 'potential'  ;D let's hope so)

oh and when i mean writing notes i mean like transcribing
everytime after i have a maths lesson

You should write as much as you need to to remember your concepts! Like, if you need to have a set of notes specifically proving differentiation by first principles, then have that. It's all about whatever works for you! :)

That said, whatever your choice, you need to be doing practice as well. No one ever got a strong result in a HSC Math subject without doing any practice at all. Do what you need to do, but make sure practice is mixed in :)

jamesq

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Re: Mathematics Question Thread
« Reply #897 on: November 11, 2016, 11:17:11 pm »
0
A loan of $6000 over 5 years at 15% p.a. interest, charged monthly, is paid back in 5 annual instalments.
(a) What is the amount of each instalment?

Answer is $1835.68.
I tried the question and got $1712.87, any help is appreciated. Thanks in advance!
2017: Advanced English, 3U Maths, Biology, Chemistry, IPT

jamonwindeyer

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Re: Mathematics Question Thread
« Reply #898 on: November 11, 2016, 11:20:27 pm »
+1
A loan of $6000 over 5 years at 15% p.a. interest, charged monthly, is paid back in 5 annual instalments.
(a) What is the amount of each instalment?

Answer is $1835.68.
I tried the question and got $1712.87, any help is appreciated. Thanks in advance!

Hey James! So two steps here; find the total amount owed, and then divide that into the 5 repayments :) I'd be happy to lend a hand, but we need to know whether this is simple interest or compound interest? Indeed, perhaps you used the wrong one in your working? Or did the question not say? :)

If you let me know whether its simple or compound I'd be happy to show you the working for it! ;D

Edit: Yeah actually, sorry, these are always compound. That said, reckon you could snap a pic of your working and pop it as an attachment?Since you are close I reckon you might have just made a small mistake, I'll try and spot it for you! :)
« Last Edit: November 11, 2016, 11:26:43 pm by jamonwindeyer »

RuiAce

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Re: Mathematics Question Thread
« Reply #899 on: November 11, 2016, 11:33:02 pm »
+1
A loan of $6000 over 5 years at 15% p.a. interest, charged monthly, is paid back in 5 annual instalments.
(a) What is the amount of each instalment?

Answer is $1835.68.
I tried the question and got $1712.87, any help is appreciated. Thanks in advance!





Hey James! So two steps here; find the total amount owed, and then divide that into the 5 repayments :) I'd be happy to lend a hand, but we need to know whether this is simple interest or compound interest? Indeed, perhaps you used the wrong one in your working? Or did the question not say? :)

If you let me know whether its simple or compound I'd be happy to show you the working for it! ;D

Edit: Yeah actually, sorry, these are always compound. That said, reckon you could snap a pic of your working and pop it as an attachment?Since you are close I reckon you might have just made a small mistake, I'll try and spot it for you! :)
When you're an actuary and just chuck it into the present value formula before doing the question 8)
« Last Edit: November 11, 2016, 11:36:07 pm by RuiAce »