If Ann saves x dollars each week and Beth saves y dollars each week, what is the total amount that they save per week?
(1) Beth saves $5 more per week than Ann saves per week.
(2) It takes Ann 6 weeks to save the same amount that Beth saves in 5 weeks.
DS: 1
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IMO C
(1) Beth saves $5 more per week than Ann saves per week.
NOT SUFF
2)It takes Ann 6 weeks to save the same amount that Beth saves in 5 weeks
LCM is 30
if we take multiples of 30: 30,60,90,120,150,180...
we get X=5,Y=6 or X=10,Y=12...so on
NOT SUFF
combined,
the only value possible is 150
where X=25, Y=30
they save 55 dollars per week
SUFF
(1) Beth saves $5 more per week than Ann saves per week.
NOT SUFF
2)It takes Ann 6 weeks to save the same amount that Beth saves in 5 weeks
LCM is 30
if we take multiples of 30: 30,60,90,120,150,180...
we get X=5,Y=6 or X=10,Y=12...so on
NOT SUFF
combined,
the only value possible is 150
where X=25, Y=30
they save 55 dollars per week
SUFF
The powers of two are bloody impolite!!

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Solution:
Question Stem Analysis:
We need to determine the total amount Ann and Beth save each week, given that Ann saves x dollars each week and Beth saves y dollars each week. That is, we need to determine the value of x + y.
Statement One Alone:
This tells us that y = x + 5. However, without knowing the value of either x or y, we can’t determine the value of x + y. Statement one alone is not sufficient.
Statement Two Alone:
We see that 6x = 5y. However, without knowing the value of either x or y, we can’t determine the value of x + y. Statement two alone is not sufficient.
Statements One and Two Together:
With the two statements, we have two linear equations and two variables. Note that neither equation is dependent on the other, which means that one equation is not a linear multiple of the other. Thus, we can determine the values of x and y and hence the value of x + y. Both statements together are sufficient.
Answer: C
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