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A&B

by Suyog » Mon Nov 26, 2007 9:51 pm
if AB = 40, what is the value of AB(A + 2B)
1. A - B = -18
2. A^2B = 80
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by sujaysolanki » Tue Nov 27, 2007 1:19 am
if this question is taken as a ^2b i.e a raised to 2b

From 1 a and b have to be 2 and 20 ..So sufficient

From 2 a = 80 b = 1/2
a = 6400 b = 1/4

Hence it shd be A ..whats the OA ?


if it is taken as a^2 b i.e a squared *b ..then it shd be B
Last edited by sujaysolanki on Tue Nov 27, 2007 4:09 am, edited 1 time in total.
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by syv11 » Tue Nov 27, 2007 6:04 am
Shouldn't 1 be enough in any case ie the right answer be A or E?
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by samirpandeyit62 » Tue Nov 27, 2007 7:02 am
if AB = 40, what is the value of AB(A + 2B)
1. A - B = -18

A = -20 b =-2, A= 2, B=20 INSUFF

2. A^2B = 80

AB *A =80, so A =2 B =20 SUFF

B
Regards
Samir
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by lawalx » Tue Nov 27, 2007 10:21 pm
hi samir

ow did u gt AB*A from A^2B
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by camitava » Tue Nov 27, 2007 10:41 pm
Guys, this type of Qs sometimes confuses the test-taker -
if AB = 40, what is the value of AB(A + 2B)
1. A - B = -18
2. A^2B = 80
Now we have ab = 40 and by stmt - 1 a - b = -18. So we can get easily a + b . But mind it - a + b can be a +ve or -ve number. Depending upon whether a + b is +ve or -ve, values for a and b can be different. So leave this stmt.
From stmt - 2, we are directly getting the value of a and hence B from ab = 40.
So it should be B only.
Correct me If I am wrong


Regards,

Amitava
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