integers

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Source: — Data Sufficiency |

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by cramya » Fri Jun 19, 2009 6:58 pm
Square wats given

a^3-a^2-b=49

a^2 (a-1) = b+49

Stmt I

a (a-1) = 12

a=-3 we can find a b value that satisfies the above condn
or
a=4 we can find a b value thats satisfies the above condn

INSUFF

Stmt II

b (b-1) = 2

b can be -1 or 2

If b= -1 we get a^2 (a-1) = b+49
a^2 (a-1) = 48

a=4

But when b=2 we get a^2 (a-1) = 51 (Not possible since a has to be an integer satisfying this condition 51 has 4 factors 1,3,17,51)

so a=4

hence b

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by abhinav85 » Sat Jun 20, 2009 6:06 am
Hey Cramya

Stmt II

b (b-1) = 2

b can be -1 or 2


If b= -1 we get a^2 (a-1) = b+49
a^2 (a-1) = 48

a=4


Should'nt the value of b be b=2 or b=3???