How much pure antifreeze must be added to 12 L of a 40% solution to obtain a 60% solution. (Remember that pure antifreeze is 100% = 1.) What is the correct question to solve this problem?

Question

How much pure antifreeze must be added to 12 L of a 40% solution to obtain a 60% solution. (Remember that pure antifreeze is 100% = 1.)  What is the correct question to solve this problem?

anonymous · Answer

add 6 L

anonymous · Answer

10.8/18

ash2326 · Answer

let the amount added be x litres
12 L of a 40 % solution has 4.8 litres of antifreeze
(4.8+x)/ (12+x) *100=60
4.8+x=0.6(12+x)
4.8+x=7.2+0.6x
0.4x=2.4
x=6 litres

anonymous · Answer

6 litres

hero · Answer

x + 12 = y
x + .40(12) = .60y

hero · Answer

Satellite, congratulations on getting 10,000 medals

anonymous · Answer

$$.4\times 12+x=.6(12+x)$$ solve for x
thank you!!!

anonymous · Answer

Wow, that's cool! 10000 medals!!!

anonymous · Answer

kind of silly, huh?

hero · Answer

Yup. You're officially the Godfather of OS

anonymous · Answer

What's silly?

anonymous · Answer

yeah, but haven't moved up a level since august

hero · Answer

lol

anonymous · Answer

You can't right?

anonymous · Answer

really.  i think it is impossible. no matter though.

anonymous · Answer

For users who are below lvl 100, the bar on the right corner shows how far you are from the next lvl. What does it look like when you're lvl 100? Can you post the picture satellite, just curious.....

anonymous · Answer

satellite do you work here? How long has it taken you to get so many medals?!

anonymous · Answer

He's not a mod....

hero · Answer

Satellite was here before OS was OS as we know it.

anonymous · Answer

Satellite, can you post the pic please....

hero · Answer

Where's muffin?

anonymous · Answer

What muffin?