algebra
posted by Rachelle on .
5 green balls and 2 red balls together weigh 10 pounds, and 1 green ball and 4 red balls together weigh 7 pounds. If all red balls weigh the same amount and all green balls weigh the same, then what is the weight of 8 red and 8 green balls together?
I'm not sure at all how to solve this one, either... please help in any way you can! Thanks! :)

i kinda did ratios
5:2 =10
4:1 =7
8:8 =?
so then
2 1/2:1 =5
2:1/2 =3 1/2
4:4 =? 
The red ball weighs about 1.4
the green ball weighs about 1.44
So i think 8r and 8g ball weighs about 22.72
This is not an exact measurement of each balls, just an estimate. 
Wow... 1/2 of a ball. :)
I see what you were trying to get across... but our teacher never showed us a problem like this... so frustrating.
I don't know if your ratio way is exactly right, but it is a good way to straighten out the info.
Wait... I got something!
Maybe it's...
g is green and r is red.
5g + 2r = 10
g + 4r = 7
Then, if we add those together and find out what one ball weighs individually, then you just multiply it by 8! I think I got it! :) 
thanks chopsticks.
yeah that makes sense... i'm gonna try it. 
Yes, Chopsticks, after trying the way I described in my last response, I got the same answers you have.
Thank you for your help! :) 
i reposted it btw ok? :):):) just so you know.