andrewh wrote:

1) (n^2)y = 100

2) n= 5 and y = 4

This question is from

Total GMAT Math. The statement (1) provides that (n^2)y = 100 which implies that n(y^(1/2)) can be either 10 or -10. However, the solution provided by the book states that the above value is only 10. Hence I chose B, sine the statement (1) can be both 10 or -10. Is my approach incorrect?

The official answer is D.

Thanks in advance for your expertise!

Given that

(x/y)power(1/2) = n

x/y = n square

x = y. n square

now,

1. y.nsquare = 100

sufficient

2. values for Y and N are given, then this is sufficient too...

so my ANSWER is D

_________________

Regards,

Harsha

Note: Give me kudos if my approach is right , else help me understand where i am missing.. I want to bell the GMAT Cat

Satyameva Jayate - Truth alone triumphs