During a 10-week summer vacation, was the average

Question

During a 10-week summer vacation, was the average (arithmetic mean) number of books that Carolyn read per week greater than the average number of books that Jacob read per week?

(1) Twice the average number of books that Carolyn read per week was greater than 5 less than twice the average number of books that Jacob read per week.
(2) During the last 5 weeks of the vacation, Carolyn read a total of 3 books more than Jacob.

Himalayan · Answer

E. 

1: 2c > (2a - 5)

if c = 5, and a = 5, 2c > (2a-5)
if c = 3, and a = 5, 2c > (2a-5)
if c = 6, and a = 5, 2c > (2a-5)

2: it says nothing.

sumande · Answer

Thanks Himalayan. I also came up with E, but the OA was A !!

Guess, it must be wrong.

ywilfred · Answer

Let number of books Carolyn reads be C
Let number of books Jacob reads be J

St1:
2(C/10) = 2(J/10)-5
(c/10) = (J/10)-5/2 <--- Carolyn reads less books per week on average 
Sufficient.

St2:
Insufficient. We do not know who read more/less during the first five weeks.

Ans A

sumande · Answer

Statement 1 says  "greater than" , not  "equal to" .

ywilfred · Answer

okay, I see where you're going. I failed the read the part 'Twice the average number of books that Carolyn read per week was greater than 5 less than twice the average number of books that Jacob read per week.' So the equation should be C/10 > J/10 + 5/2. So we can't solve for because C could be more or less than J. Error on my part. sorry everyone. :oops:

ioiio · Answer

E.

c > J - 2.5 == useless
St. 2 == even more useless (No wonder my verbal scores are showing a downward trend)

During a 10-week summer vacation, was the average

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