Necessary assumption. Usenegation. I said these two sentences hundreds of times here. If you master thetechnique of negation, you should be able to solve the necessary assumptionproblems easily and pass GMAT with flying colors.
When you negate an answer, just negate it. Try not to turn it into itsopposite. Also, negate either the verb or the quantity, but not both.
To negate an if-thenstatement, negate ONLY the then clause.So "if A, then B" would become "if A, then not B"
Quantitites | Negation
all, any,each, every, always | not all, some arenot
most,majority | not most
usually,likely | not usually, not likely
some,many, few | none
sometimes,often, rarely | never
only one,only once | more than one, none (That's right. Not one = none or more thanone)
exactlytwo | one, more than two,none (similar to the reason listed above)
no, none | some
Verbs | Negation |