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#1 Help Me ! » Percentages » 2009-04-15 20:07:34

Shmeeztut
Replies: 5

Please help me with these two questions, I don't really understand what the difference is. ><

In 2004, the cost of organizing the concert was $385.

In 2005 the cost was 10% less than in 2004.

Calculate the cost in 2005.


And then the next question on the paper...


The cost of $385 in 2004 was 10% more than the cost in 2003.

Calculate the cost in 2003.

#2 Help Me ! » Impossible Algebra? » 2009-04-15 00:03:32

Shmeeztut
Replies: 1

My friend told me about this, and I just don't get how it works!

x = y

Times x to both sides.

x² = xy

Times -y^2 to both sides.

x² - y² = xy - y²

Factorise.

(x + y )(x - y) = y(x - y)

Then... divide both sides by (x - y).

x = x + y?!

How is this possible? The algebra is correct as far as I can see.








da frend hu told mi is super cool and awesome

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