Author Topic: Math Q  (Read 1738 times)

Offline XIII_BD

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Math Q
« on: February 12, 2010, 10:49:14 am »
How many gallons of distilled water must be mixed with 50 gallons of 30% alchohol solution, to obtain a 25% solution.

pls help me out here u guys....

Offline astarmathsandphysics

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Re: Math Q
« Reply #1 on: February 12, 2010, 12:19:07 pm »
There are 15 gallons water to start.Suppose x gallons are added, the amount of solution is 50+x
(15)/(x+50)=0.25
15=0.25x+12.5
0.25x=2.5 so x=10

Offline SGVaibhav

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Re: Math Q
« Reply #2 on: February 13, 2010, 08:39:03 am »
omg this looks so easy, but its still hard :P

Offline Saladin

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Re: Math Q
« Reply #3 on: February 13, 2010, 08:56:04 am »
dude, that integration question that u posted, it was soooo damn funny

i cud not stop laughing man

hehe

Offline SGVaibhav

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Re: Math Q
« Reply #4 on: February 13, 2010, 09:16:47 am »
dude, that integration question that u posted, it was soooo damn funny

i cud not stop laughing man

hehe

mee???
lol which one??

Offline Saladin

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Re: Math Q
« Reply #5 on: February 13, 2010, 05:16:41 pm »
The integration question like where u cud not get why it was 2 instead of 4, and it was basically cuz u 4got to sq.rt.

nid404

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Re: Math Q
« Reply #6 on: February 16, 2010, 05:33:51 pm »
This is like serial dilutions......we have it in bio

50 gallons of 30% acohol solution
15 gallons of alcohol
v1c1=v2c2
50X30=V2X25
V2=60gallons

So 10 litres of water to be added....
Actually the same thing as astar but mabe this should make it easier