Age?

[brick2009]

Q9:How many years did Dr. Jones live?
(1) If Dr. Jones had become a doctor 10 years earlier than he did, he would have been a
doctor for exactly 2/3 of his life.
(2) If Dr. Jones had become a doctor 10 years later than he did, he would have been a doctor
for exactly 1/3 of his life.


OA: C

How????

[anandr84]

D= no of years jones was a doc
T= total number of years he lived

1> D+10 = (2/3)T
INSUFFICIENT

2> D-10 = (1/3)T
INSUFFICIENT

1 & 2> Solving the simultaenuous equations we can get T

[brick2009]

..even i had arrived at that equation..but when you go ahead and solve it...you get 2D = T.

i think the answer is wrong>>>>

D= no of years jones was a doc
T= total number of years he lived

1> D+10 = (2/3)T
INSUFFICIENT

2> D-10 = (1/3)T
INSUFFICIENT

1 & 2> Solving the simultaenuous equations we can get T

[jaspreet_takhar]

..even i had arrived at that equation..but when you go ahead and solve it...you get 2D = T.

i think the answer is wrong>>>>

D= no of years jones was a doc
T= total number of years he lived

1> D+10 = (2/3)T
INSUFFICIENT

2> D-10 = (1/3)T
INSUFFICIENT

1 & 2> Solving the simultaenuous equations we can get T

Subtract Eq 2 from eq 1,u'll get T = 60

[brick2009]

awwww.. true...
this is just great..weeks before the exam.. i forget the fundamentals..

..even i had arrived at that equation..but when you go ahead and solve it...you get 2D = T.

i think the answer is wrong>>>>

D= no of years jones was a doc
T= total number of years he lived

1> D+10 = (2/3)T
INSUFFICIENT

2> D-10 = (1/3)T
INSUFFICIENT

1 & 2> Solving the simultaenuous equations we can get T

Subtract Eq 2 from eq 1,u'll get T = 60

[JeffB]

I wouldn't have even wasted my time trying to solve for T. You have (2) equations and (2) unknowns.

[grockit_jake]

yes, no need to plug in and solve on data sufficiency questions.

If there are 2 linear eqs and 2 unknowns (that are not identical multiples of each other) then you have a unique solution.