DS variables

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DS variables

by karthikpandian19 » Thu Jun 07, 2012 9:51 pm
Last year, Department A earned 35% more than department B did. Is department A's earnings this year higher than department B's last year's earnings?

(1) Department B earned $1,002,035 last year

(2) Department A earned 35% less this year then it did last year
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by Anurag@Gurome » Thu Jun 07, 2012 10:25 pm
karthikpandian19 wrote:Last year, Department A earned 35% more than department B did. Is department A's earnings this year higher than department B's last year's earnings?

(1) Department B earned $1,002,035 last year
(2) Department A earned 35% less this year then it did last year
Statement 1: No information about A's earnings in this year ---> Not sufficient

Statement 2: No information about B's earnings in last year ---> Not sufficient

1 & 2 Together: From statement 1, we know B's earnings in last year.
From statement 2 and question stem we can determine A's earning in this year.
Hence, we can determine whether A's earning in this year is higher than B's earnings in last year or not.

Sufficient

The correct answer is C.
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by karthikpandian19 » Thu Jun 07, 2012 11:07 pm
OA is B
Anurag@Gurome wrote:
karthikpandian19 wrote:Last year, Department A earned 35% more than department B did. Is department A's earnings this year higher than department B's last year's earnings?

(1) Department B earned $1,002,035 last year
(2) Department A earned 35% less this year then it did last year
Statement 1: No information about A's earnings in this year ---> Not sufficient

Statement 2: No information about B's earnings in last year ---> Not sufficient

1 & 2 Together: From statement 1, we know B's earnings in last year.
From statement 2 and question stem we can determine A's earning in this year.
Hence, we can determine whether A's earning in this year is higher than B's earnings in last year or not.

Sufficient

The correct answer is C.
Last edited by karthikpandian19 on Fri Jun 08, 2012 2:15 pm, edited 1 time in total.
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by Ashujain » Fri Jun 08, 2012 5:19 am
Why is B wrong?

Lets assume B's last year income = B
Then A's last year income = 1.35B
And A's income this year = 0.65 * 1.35 B (as per statement 2) = 0.8775 B

Therefore, statement 2 is sufficient as it provides a definite answer that A's this year income is less than B's last year income.

Kindly correct me if I am wrong.

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by khandelwal.ab » Fri Jun 08, 2012 5:46 am
I dont understand why B is not the answer...

Statement2-> department a earned 35% less this year then it did last year.

Information we have using the stem and statement 2 alone:

Earnings of B last year- b (b is an unknown variable)
Earnings of A last year- 1.35b
Earnings of A this year- 1.35b-(1.35b*0.35)= 0.877b

0.877b<b.... hence B is sufficient..

please let me know if I am missing something here.

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by eagleeye » Fri Jun 08, 2012 7:39 am
khandelwal.ab wrote:I dont understand why B is not the answer...

Statement2-> department a earned 35% less this year then it did last year.

Information we have using the stem and statement 2 alone:

Earnings of B last year- b (b is an unknown variable)
Earnings of A last year- 1.35b
Earnings of A this year- 1.35b-(1.35b*0.35)= 0.877b

0.877b<b.... hence B is sufficient..

please let me know if I am missing something here.
khandelwal.ab, Ashujain: You guys are both right. The OA provided is wrong. It should be B.
In option (1), what B earned last year actually adds no useful information to the question.

As you guys have pointed out, from the question stem, we know that A(last year)= 1.35*b(last year).
And option (2) is A(this year) = 0.65* A(last year) = 0.65*1.35*b(last year) = 0.8775*b(last year).
Clearly, we can tell that A earned less this year than what B earned last year.

karthikpandian19, please correct the OA to be B.

Let me know if this helps :)

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by karthikpandian19 » Fri Jun 08, 2012 2:15 pm
done
eagleeye wrote:
khandelwal.ab wrote:I dont understand why B is not the answer...

Statement2-> department a earned 35% less this year then it did last year.

Information we have using the stem and statement 2 alone:

Earnings of B last year- b (b is an unknown variable)
Earnings of A last year- 1.35b
Earnings of A this year- 1.35b-(1.35b*0.35)= 0.877b

0.877b<b.... hence B is sufficient..

please let me know if I am missing something here.
khandelwal.ab, Ashujain: You guys are both right. The OA provided is wrong. It should be B.
In option (1), what B earned last year actually adds no useful information to the question.

As you guys have pointed out, from the question stem, we know that A(last year)= 1.35*b(last year).
And option (2) is A(this year) = 0.65* A(last year) = 0.65*1.35*b(last year) = 0.8775*b(last year).
Clearly, we can tell that A earned less this year than what B earned last year.

karthikpandian19, please correct the OA to be B.

Let me know if this helps :)
Regards,
Karthik
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by eagleeye » Fri Jun 08, 2012 4:56 pm
Thanks karthikpandian19. :)

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by ronnie1985 » Sat Jun 09, 2012 10:48 am
A = 1.35*B

S1:B=given value. No info about A next year. NS

S2: A = 0.65*1.35B = (x)B x is known. Suff to answer a yes or no

(B)
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by bubbliiiiiiii » Mon Jun 11, 2012 3:25 am
+1 for B.
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