Maths Game (1 Viewer)

pwoh

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:p Same here, I always get the easy questions wrong by doing something stupid.

Someone else provide questions please?
 

Somnolence

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Simplify (Non-Calculator)

321*23*9
________
642*69*5

This is a similar question to one we had in our trials. To some it may appear difficult, but once you look at it closely, it is really easy.
 

pwoh

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Somnolence said:
Simplify (Non-Calculator)

321*23*9
________
642*69*5

This is a similar question to one we had in our trials. To some it may appear difficult, but once you look at it closely, it is really easy.

1*23*9
________
2*69*5

1*23*3
________
2*23*5

3/10
 

suzlee

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Air Jordan said:
[log(base 2)x] + [log(base 2) (x²-4)] - [log(base2)(x+2)] = 3


logarithm is an optional topic. It's not gonna be in the SC............................
 

suzlee

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pwoh said:
o_o; Is log a part of one of the optional topics?

We haven't done it yet. Someone else answer...

I haven't done it either. Yes it is optional, along with polynomials, circle geometry, etc
 

pwoh

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suzlee said:
logarithm is an optional topic. It's not gonna be in the SC............................
I wonder if there's someone who can answer that anyway.

Jenni bought 30CDs and DVDs for a total of $855. Each CD cost $20 and each DVD cost $35. How many of each did she buy?
 

suzlee

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pwoh said:
I wonder if there's someone who can answer that anyway.

Jenni bought 30CDs and DVDs for a total of $855. Each CD cost $20 and each DVD cost $35. How many of each did she buy?


yay finally a SC question :)


number of CDs = x

855 = 20x + 35(30-x)
855 = 20x + 1050 - 35x
195 = 15x
13 = x


She bought 13 CDs and 17 DVDs





oh yeah I'll post a question:
Four years ago, I was twice as old as I was 14 years ago. What is my age?
 

Miss Sunshine

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age now= x

x-4=2(x-14)
x-4=2x-28
x+24=2x
x=24

Therefore 4 years ago I was 20

14 years ago i was 10

So double 10 is 20

Your age now is 24.
 

Kabuzo01

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I cant be bothered updating points yet... Too busy with the school thread =P
 

Lukybear

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Air Jordan said:
[log(base 2)x] + [log(base 2) (x²-4)] - [log(base2)(x+2)] = 3
Might be wrong but:
log(base2)((x(x^2-4))/x+2))=3
8=x(x^2-4)/x+2
(factorise)
x(x-2)(x+2)/x+2=8
x^2-2x-8=0
factorise
x=4 or -2

is that rite?
 

lyounamu

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Lukybear said:
Might be wrong but:
log(base2)((x(x^2-4))/x+2))=3
8=x(x^2-4)/x+2
(factorise)
x(x-2)(x+2)/x+2=8
x^2-2x-8=0
factorise
x=4 or -2

is that rite?
Haven't read your whole working out but you cannot have x=-2.
 
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Lukybear said:
Might be wrong but:
log(base2)((x(x^2-4))/x+2))=3
8=x(x^2-4)/x+2
(factorise)
x(x-2)(x+2)/x+2=8
x^2-2x-8=0
factorise
x=4 or -2

is that rite?
no

3
 
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lyounamu said:
You are wrong. I just did the question.

I am sure it's x=4.
Oh. Okay then



where did the 8 come from?
cant find out how
 
Last edited:

lyounamu

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xXmuffin0manXx said:
Oh. Okay then



where did the 8 come from?
cant find out how
Would you like to elaborate on that? I don't understand what you mean.
 

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