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If Bob produces 36 or fewer items in a week,

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sk
 Post subject: If Bob produces 36 or fewer items in a week,
 Post Posted: Sun Aug 10, 2008 7:27 pm 
If Bob produces 36 or fewer items in a week, he is paid x dollars per item. If Bob produces more than 36 items in a week, he is paid x dollars per item for the first 36 items and 1 1/2(1.5) times that amount for every additional item.
How many items did Bob produce last week?

(A) Last week Bob was paid a total of $480 for the items he produced that week.

(B) This week Bob produced 2 more items than last week and was paid a total of $510 for the items that he produced this week.
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Guest
 Post subject:
 Post Posted: Mon Aug 11, 2008 10:40 am 
What is the OA?
Thanks.
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sk
 Post subject: If Bob produces 36 or fewer items in a week,
 Post Posted: Mon Aug 11, 2008 1:36 pm 
OA is E.
As per my understanding, it should be C.
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suk
 Post subject:
 Post Posted: Mon Aug 11, 2008 10:35 pm 
Both 1) and 2) can result in two equations

1. 36 items * 10 dollars + y items * 15 dollars = 480

As from 2) we know that USD 30 more were generated by selling 2 more items, USD 15 was the price per item, hence the resulting values


2. x items * 15 dollars = USD 510

x items = 510/15 = 34. Hence for 34 items, a constant price of 15 dollars was charged.


Hence USD 15 can be the price for less than 36 items as well.

Therefore both 1) and 2) are INSUFFICIENT, hence E
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RonPurewal
 Post subject:
 Post Posted: Thu Aug 14, 2008 4:53 am 
Offline
ManhattanGMAT Staff


Posts: 7146
suk wrote:
Both 1) and 2) can result in two equations

1. 36 items * 10 dollars + y items * 15 dollars = 480

As from 2) we know that USD 30 more were generated by selling 2 more items, USD 15 was the price per item, hence the resulting values


2. x items * 15 dollars = USD 510

x items = 510/15 = 34. Hence for 34 items, a constant price of 15 dollars was charged.


Hence USD 15 can be the price for less than 36 items as well.

Therefore both 1) and 2) are INSUFFICIENT, hence E


well played. for the first case, it is ESSENTIAL that you calculate y, though: y = 8.
unlike most DS equations, this one depends upon "y" being an integer; if you solve the equation and y turns out NOT to be an integer, then that's actually not a solution at all.
because y actually works out to an integer, this is a legitimate second solution.
so, to recap, this problem works out with EITHER
(1) 36 items @ $10 each, 8 items @ $15 each, 2 add'l items @ $15 each
OR
(2) 32 items @ $15 each, 2 add'l items @ $15 each
so, insufficient.

i like this problem.
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guest
 Post subject:
 Post Posted: Sat Aug 16, 2008 9:49 am 
can u pls explain the second part a bit more in detail.i did not understand that part.
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RonPurewal
 Post subject:
 Post Posted: Mon Aug 25, 2008 5:24 am 
Offline
ManhattanGMAT Staff


Posts: 7146
guest wrote:
can u pls explain the second part a bit more in detail.i did not understand that part.


sure.

if bob produces 32 items at $15 each, that's a total of $480, as stipulated by statement (1).
however, because he hasn't reached the threshold level of 36 items yet, bob will still only get $15 per item for the 33rd and 34th items. adding these on, we get a total of $510, as required.
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