In your laboratory is a 18 liter solution of water and oil

Question

In your laboratory is a 18 liter solution of water and oil that is presently made up of 2 parts water to 4 parts oil. How many liters of water must you add to the solution so that it becomes 4 parts water to 4 parts oil? 

A. 6
B. 7
C. 8
D. 9
E. 10

Yurik79 · Answer

A it is
the total mixture should contain 4 parts of oil and 4 parts of water total 8
total mixture must be multiple of 8
6+18=24 bingo

andy_gr8 · Answer

A it is..

Current ration W: O=1:2=> Water =6, Oil=12
Add x water
means 
6+x/12=1/1=>x=6

ps_dahiya · Answer

Now:
W: O = 1:2 i.e 6:12

To make it 1:1 we need 6 more litre of water.

lhotseface · Answer

2x+4x=18 => x = 6. To mantain the 4:4 or 1:1 ratio we need _ + 12 = 12 +12 =24. Thus 12-6 = 6 more litres need to be added.

sperumba · Answer

2x+4x = 18

Therefore 6x = 18 => x =3

sollution has 6 parts water adn 12 parts oils.

now if we add x water 

water becomes 6+x, oild remains 12 and total becomes 18 +x.

for a 4:4 ratio (1:1) ratio

6+x = 12 therefore x = 6 

or 

6+x = (18+x)/2 => x = 6.

So A is the answer

GMATT73 · Answer

Good work guys.

OA is A.

In your laboratory is a 18 liter solution of water and oil

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