Is (m + z) > 0?

1) m - 3z > 0

2) 4z - m > 0

Posted: Fri Aug 10, 2007 2:40 pm


Is (m + z) > 0?

1) m - 3z > 0

2) 4z - m > 0

1 tells m > 3z , not suffecient
2 tells z > m/4 not sufficient.

Add both the ineq's (Add is fine). Gives z > 0
since m > 3z, z>0 so m>0

Hence m+z > 0

Answer is C.

that you can add the inequalities if they have same sign, either both > or both <.

wonderful explanation. (C) is the correct answer.