Is a

Question

Is  a < b  ?

(1)  a^3 = −27  and  b^2 = 9

(2)  a = \sqrt {−27}  and  b = √ 9

This is a  Data Sufficiency Butler Question

Check the links to other Butler Projects: 
 
   Data Sufficiency Butler 
   Problem Solving Butler  
   Sentence Correction Butler  
   Reading Comprehension Butler  
   Integrated Reasoning Butler

VivekSri · Answer

Is a<b

(1)  a{3} =−27 and b2=9
 If  a{3} =−27 then a = -3
and  b{2}  = 9 then b can be -3 or 3

So we can not be sure whether b > a so not sufficient.

(2) a = \sqrt \sqrt{-27}

this clearly means a = -3

and b=√9

Since number cannot be negative in roots so b will be 3.

So (2) is sufficient to answer the question.

So B is true

ostrick5465 · Answer

(1) => (1)  a = −3 , and  b = 3  or  b = -3 
=> Insuff

(2) =>  a = −3  and  b = 3 
=> Suff

=> IMO B

Is a < b ? (1) a^3 = 27 and b^2 = 9 (2) a = (27)^(1/3) and b = 9

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia