DS - What is the value of b?

Question

This is a data suffiency question.

If 2b - 2a^2 = 18, what is the value of b?

1. a^2 = 1156

2. a> 0

Which statement is suffiencient to answer the question?

Thanks

richardj · Answer

1. is sufficient. A

Since (1) gives you a^2, the sign of a isn't needed to answer the question.
But (2) alone gives you a range for b.

macca · Answer

I'd pick A

Statement 1 gives you a^2=1156.
Just substitue that into the equation and you'll get a value for b.

2. Insufficient, you only know that a is greater than 0. a could be anything
so you cannot solve for b. 

If 2b - 2a^2 = 18, what is the value of b? 

1. a^2 = 1156 

2. a> 0

need700111 · Answer

A clearly

same raesoning as others

Antmavel · Answer

A.

You just need A^2 to find B so no need of statement 2

Raman Jit Kumar · Answer

Since we have (1) as a^2=1156, we can substitute the value and have the answer.

Definetely, A is the pick

DS - What is the value of b?

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