I cannot figure this out for some reason

A 100% concentrate is to be mixed with a mixture having a concentration of 40% to obtain 55 gallons of a mixture with a concentration of 75%. How much of the 100% concentrate will be needed?

the answer is about 32.1 gallons but how do you get there?

100(x) + 40(55-x) = 75(55)

Attaboy Alec

just double checked and it worked.

100x + 2200 - 40x = 4125

60x = 1925

x = 32.083333

32.08333333333333333

to be exact ;)

what the crap! :eek: i did everything right but the 75(55)

Thanks alot!!!!!!

You have to start with 100x + 40y = 75z.

They you figure out that you can plug in known values for y and z, left with a single variable.

Hot damn! I am impressed, Alec. I wish I had you guys to ask when I was still in college.

thats a college question? i want to go take that class

Seriously, I did that in 3rd grade or b4 ;)