A simple confusion

[prankyshashank]

col a 7+sqrt(49)
col b 5+ sqrt(25)

why i am asking this w\question as i have read in one of the forums that if the case is of sqrt(x^2) then we are ought to take positive value of x but this is a question from barons and the answer was given to be d please guide what will be the answer according to ets

[walt526]

Well first, please post topics in the proper subforums, not the main GRE forum (it's questions about the test, not subject matter--you asked a verbal question in the main one earlier tonight as well).

To answer this question:
sqrt(49)=+7 (only, not -7)
sqrt(25)=+5 (only, not -5)

Thus, A=7+7=14 and B=5+5=10. Therefore, obviously A>B.

This is a very easy arithmetic question that's simply testing whether you understand the concepts of square roots and addition. There's no trick.

[sloggy_doggy]

sqrt(49)=+7 (only, not -7)
sqrt(25)=+5 (only, not -5)

@walt: why consider only +7 and +5...cant the answer be 'D' if the values are taken as "+-7" and "+-5"...i am confused..please tell me how i can differentiate problems where in we should only consider the +ve root and ones in which we should consider the +-roots...thanx..

[walt526]

sqrt(49)=+7 only

But if x^2=49, then x=+/-7

[sloggy_doggy]

thanks alot walt...that was helpful..

[shrivipha]

Walt's right. For GRE, when they say square root, it means the positive square root. That's their rule.