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Algebra Problem

Hi guys, I need help with this question.

In a particular country there are two political parties, the Red Party and the Blue Party. Prior tolast week's General Election the Red Party had times as many representatives in theparliament as the Blue Party. The Red Party's lead has been reduced by 56 as a result of theGeneral Election, but it now has times as many representatives as the Blue Party.
How many seats are there in the parliament?

So since the Red party has 2.5times as many people as the blue party, I did 2.5x+1x=T (for total people in the government).
Then after wards, I did 1.5x+1x+56=T
After solving for I got the total as 196, which I wrong. So I'm wondering where I wen't wrong?
Thanks!
Original post by ΘTheta
Hi guys, I need help with this question.

In a particular country there are two political parties, the Red Party and the Blue Party. Prior tolast week's General Election the Red Party had times as many representatives in theparliament as the Blue Party. The Red Party's lead has been reduced by 56 as a result of theGeneral Election, but it now has times as many representatives as the Blue Party.
How many seats are there in the parliament?

So since the Red party has 2.5times as many people as the blue party, I did 2.5x+1x=T (for total people in the government).
Then after wards, I did 1.5x+1x+56=T
After solving for I got the total as 196, which I wrong. So I'm wondering where I wen't wrong?
Thanks!

The *lead* has been reduced. That is, R-B has been reduced, not T. (I'd personally work with R and B throughout, rather than x; that makes it easier for me to remember which variable is talking about what.)

It may help to draw a picture. A rectangle with a proportion 5:2 in favour of Red, then a rectangle below it with the swing decreased by 56, and in 3:2 ratio.
Reply 2
Original post by ΘTheta
Hi guys, I need help with this question.

In a particular country there are two political parties, the Red Party and the Blue Party. Prior tolast week's General Election the Red Party had times as many representatives in theparliament as the Blue Party. The Red Party's lead has been reduced by 56 as a result of theGeneral Election, but it now has times as many representatives as the Blue Party.
How many seats are there in the parliament?

So since the Red party has 2.5times as many people as the blue party, I did 2.5x+1x=T (for total people in the government).
Then after wards, I did 1.5x+1x+56=T
After solving for I got the total as 196, which I wrong. So I'm wondering where I wen't wrong?
Thanks!


I also got 196 ...
I must be doing the same mistake like you despite my equations being different.
Original post by TeeEm
I also got 196 ...
I must be doing the same mistake like you despite my equations being different.

It's not 196. That would mean:
R before = 140, B before = 56
Then lead reduced by 56, so the new lead is 28; that gives R = 112, B = 84.
But 112/196 is 4/7 (in particular, not 3/5).

If you work through that with x instead of 196, you should get the answer popping out at the end.
(edited 9 years ago)
Reply 4
Original post by Smaug123
The *lead* has been reduced. That is, R-B has been reduced, not T. (I'd personally work with R and B throughout, rather than x; that makes it easier for me to remember which variable is talking about what.)

It may help to draw a picture. A rectangle with a proportion 5:2 in favour of Red, then a rectangle below it with the swing decreased by 56, and in 3:2 ratio.


Hello there. Thanks for the advice, but drawing the triangles aren't really helping, sorry.

How would you solve it using equations? Thanks!
Reply 5
Original post by Smaug123
It's not 196. That would mean:
R before = 140, B before = 56
Then lead reduced by 56, so the new lead is 28; that gives R = 112, B = 84.
But 112/196 is 4/7 (in particular, not 3/5).

If you work through that with x instead of 196, you should get the answer popping out at the end.


you are probably right cause I am multitasking at present so I did not read the question carefully

the lead was cut and and not the number of reds

rep for being awake at this time!
(edited 9 years ago)
Original post by ΘTheta
Hello there. Thanks for the advice, but drawing the triangles aren't really helping, sorry.

How would you solve it using equations? Thanks!

The only way I formulated the correct equations was by drawing diagrams :P
Reply 7
Original post by Smaug123
The only way I formulated the correct equations was by drawing diagrams :P

Oh. I done something similar, but I ended up getting 490 (which is half of the answer of 245). I think it was because I used a gap of 56, where as you used 28. Why did you use 28? Thanks! :biggrin:
Original post by ΘTheta
Oh. I done something similar, but I ended up getting 490 (which is half of the answer of 245). I think it was because I used a gap of 56, where as you used 28. Why did you use 28? Thanks! :biggrin:

28, because the lead R has over B reduces by 56, which means B gains 28 and R loses 28.
Reply 9
Original post by Smaug123
28, because the lead R has over B reduces by 56, which means B gains 28 and R loses 28.

I see. Thanks!:smile:
Reply 10
Original post by ΘTheta
Hi guys, I need help with this question.

In a particular country there are two political parties, the Red Party and the Blue Party. Prior tolast week's General Election the Red Party had times as many representatives in theparliament as the Blue Party. The Red Party's lead has been reduced by 56 as a result of theGeneral Election, but it now has times as many representatives as the Blue Party.
How many seats are there in the parliament?

So since the Red party has 2.5times as many people as the blue party, I did 2.5x+1x=T (for total people in the government).
Then after wards, I did 1.5x+1x+56=T
After solving for I got the total as 196, which I wrong. So I'm wondering where I wen't wrong?
Thanks!


look at the attached question. Not the same as yours but almost ...

Enlarge the PDF solution attached.

CANON Lide.pdf


see if this modelling makes things clearer.

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