(2*) (3º) has the same value as

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(2*) (3º) has the same value as

by sanju09 » Sat Oct 08, 2011 4:16 am
For all numbers a and b, if a* = 2 a - 1 and bº = 2 b, then (2*) (3º) has the same value as
(A) 5º
(B) 6º
(C) 9º
(D) 10º
(E) 18º
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by sl750 » Sat Oct 08, 2011 4:22 am
a* = 2a-1
2* = 4-1 = 3
3' = 2*3 = 6

3*6=18
Only C 9' has the same value

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by Anurag@Gurome » Sat Oct 08, 2011 4:24 am
sanju09 wrote:For all numbers a and b, if a* = 2 a - 1 and bº = 2 b, then (2*) (3º) has the same value as
(A) 5º
(B) 6º
(C) 9º
(D) 10º
(E) 18º
a* = 2a - 1
bº = 2b
(2*)(3º) = [2(2) - 1] * [2(3)] = 3 * 6 = 18 = 2(9) = 9º

The correct answer is C.
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