How much gas is added by attendant?

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How much gas is added by attendant?

by kanha81 » Mon Mar 02, 2009 9:24 am
q: when car X pulled into the gas station, its gasoline tank was 1/3 full. How many litres of gasoline did the attendant add to gas tank?

i) attendant added enough to fill gas tank to 9/10 of its capacity
ii) when car pulled in, the gas tank had 32 litres of gasoline

a:
let g: gas tank in litres (g=1/3(x) + 2/3(x))
x: quantifier

i) 1/3 full=>2/3 empty
=>2/3*(x)=9/10*(g)
=> insuff

B, C, E

ii) 1/3*(x)=32
=>x=96
=>2/3*(x)=96
=>x=48*3=124
=> suff


is this a correct way to solve the prob? This prob is quite easy, but I get confused. Please help.
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by scoobydooby » Mon Mar 02, 2009 9:38 am
how many ltrs added by attendant?

stmnt 1: attendant filled to 9/10 capacity
or 1/3+x=9/10, can be solved for x.
sufficient. ......A or D

stmnt 2: car entered with 32 ltrs
1/3 of total capacity=32, only total capacity can be found, no how much added by the attendant. not sufficient.

only A

ps: its enough to determine if it can be solved, actual solution is not neccessary

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by kanha81 » Mon Mar 02, 2009 10:00 am
scoobydooby wrote:how many ltrs added by attendant?

stmnt 1: attendant filled to 9/10 capacity
or 1/3+x=9/10, can be solved for x.
sufficient. ......A or D

stmnt 2: car entered with 32 ltrs
1/3 of total capacity=32, only total capacity can be found, no how much added by the attendant. not sufficient.

only A

ps: its enough to determine if it can be solved, actual solution is not neccessary


I agree scoobydooby, that it is enough to show that the problem can be solved, and not actual soln, but I wanted to know how would I go about solving this problem if it were a PS question.

Also, the OA is not A. It is C
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by scoobydooby » Mon Mar 02, 2009 10:11 am
oops, thanks kanha. now i realize my mistake

stmnt 1: attendant filled to 9/10 capacity
1/3+x=9/10, solving for x we get 17/30 of the capacity
but it is just a ratio, we do not how much in litres was added
not sufficient. B/C/E


stmnt 2: car entered with 32 ltrs
1/3 of total capacity=32, only total capacity can be found which is 96 lts
we do not know how much added by the attendant. not sufficient C/E

together, we have total capacity: 96 lts. the attendant added 17/30 of capacity, or 17/30*96=54.4 ltrs

C