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Seed X costs $5 per pound and Seed Y costs $7 per pound. Seed Z is a
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16 May 2017, 11:11
Question Stats:
61% (01:38) correct 39% (02:25) wrong based on 317 sessions
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Re: Seed X costs $5 per pound and Seed Y costs $7 per pound. Seed Z is a
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16 May 2017, 11:43
Seed X costs $5 per pound and Seed Y costs $7 per pound. Seed Z is a blend of the two seeds, and 20 pounds of Seed Z contains a pounds of Seed X and b pounds of Seed Y. Is a > 10? 5*a + 7*b = Total cost a+b = total weight S1. 20 pounds of Seed Z costs less than $120 a+b= 20 > b=20a 5*a + 7*b < 120 > 5*a + 7*(20a) < 120 > 140  2a < 120 > 2a > 20 > a>10 Sufficient!S2. b < 12 b<12. Given that a+b=20 if b = 11, a<10 if b = 9, a>10 Insufficient!Hence, answer should be A.
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Re: Seed X costs $5 per pound and Seed Y costs $7 per pound. Seed Z is a
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17 May 2017, 08:32
stat1: cost is not required,, not suff
stat2: if b = 11, a=9 b = 9 , a =11. not suff
both combined not suff
ans E



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Re: Seed X costs $5 per pound and Seed Y costs $7 per pound. Seed Z is a
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18 May 2017, 10:25
This is a question of Weighted averages where X costs 5 $/pound and Y costs 7 $/pound
When a particular amount of X is added to a particular amount of Y, mixture Z results
The more the proportion of X or Y determines the inclination of average price of mixture towards per pound $ price of X or Y
S1: it says that Mixture Z costs less than 6 $ /pound (because 20 pounds of Z costs less than 120$ => per pound cost less than 6$) implying that the mixture Z should have more of X (which costs $5 /pound) than Y (which costs $7/pound) in order to make the weighted average price tilt towards the $/pound price of X (being 5$/pound) .
Hence a (proportion of X) has to have a higher number as compared to b (proportion of Y) in order to have the mixture Z cost less than $ 6/pound . Now weight of mixture Z is 20 pounds. Hence a>10 . Sufficient
S2: b<12 . This statement only talks about proportion of X and Y in Z (without mentioning anything on price) if b=3, a=17 , a>10 yes if b=11, a=9 , a/\>10 no
Insufficient
Hence Answer is A



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Re: Seed X costs $5 per pound and Seed Y costs $7 per pound. Seed Z is a
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02 Jul 2017, 10:37
Starting with the easier statement. Statement 2: b<12 ; In the final mixture of 20 if b is 11, a =9 OR if b=9, a=11. Clearly a can be more than 10 or less than 10..........Insufficient A D BCE Statement 1: cost of final mixture is less than 120 We know that a+b=20 5a+7b<120 5a+7(20a)<120 5a+1407a<120 2a<20 a<10.............Sufficient Answer is A
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Joined: 11 May 2018
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Seed X costs $5 per pound and Seed Y costs $7 per pound. Seed Z is a
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02 Jul 2018, 14:14
...and 20 pounds of Seed Z contains a pounds of Seed X and b pounds of Seed Y. Is a > 10?
If a = 10, then note that a = b. (to make up 20 pounds together) So the question also translates to : Is a > b?
If we look at the prices now, Seed X costs $5 per pound and Seed Y costs $7 per pound If a = b, then Seed Z price per pound is simply the average of Seed X and Seed Y prices per pound, which is ($5+$7)/2 = $6.
Now,  If the price of Seed Z per pound is less than $6, we know that there is more of Seed X in the mixture. So a > b.  If the price of Seed Z per pound is more than $6, we know that there is more of Seed Y in the mixture. So a < b.
Let's look at the 2 statements now..
(1) 20 pounds of Seed Z costs less than $120 It's clear that the price of Seed Z per pound is less than $6. So a > b. This statement in sufficient.
(2) b < 12 We have already established that the question translates to : Is a > b? Since b < 12 :  If I take b = 11, then a = 20  b = 9. So a < b.  If I take b = 9, then a = 20  b = 11. So a > b. This statement is insufficient as we can't establish a clear relationship between a and b.
So the answer is A.



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Re: Seed X costs $5 per pound and Seed Y costs $7 per pound. Seed Z is a
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22 Sep 2018, 12:09
Bunuel wrote: Seed X costs $5 per pound and Seed Y costs $7 per pound. Seed Z is a blend of the two seeds, and 20 pounds of Seed Z contains a pounds of Seed X and b pounds of Seed Y. Is a > 10?
(1) 20 pounds of Seed Z costs less than $120
(2) b < 12 Quote: If Seed Z were made of exactly ½ Seed X and ½ Seed Y, then the cost of Seed Z would be $6 per pound (exactly halfway between $5 and $7). So if 20 pounds of Seed Z costs $120 ($6 per pound) then a = 10 and b = 10. Statement 1 tells you that the total of 20 pounds of Seed Z is LESS than $120 so there must be more pounds of Seed X than Seed Y. This means than a must be greater than 10 and statement 1 is sufficient. Quote: Statement 2 if b = 11 then a would be 9 and the answer is no to the question. However if b = 4 then a = 16 and the answer is yes. Statement 2 is not sufficient and the answer is A.



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Re: Seed X costs $5 per pound and Seed Y costs $7 per pound. Seed Z is a
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11 Nov 2018, 06:19
X+Y=20 i.e. ab+b=20
Stmt 1 20 pounds cost less than 120 lets say a =b=10 cost =120 for the total to cost less than 120
logically a needs to be greater than b as a costs less than b
stmt 2  b can be 11 or 9 so we cant comment on whether a>b or b>a




Re: Seed X costs $5 per pound and Seed Y costs $7 per pound. Seed Z is a &nbs
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