Free GMAT Course > Critical Reasoning > Modify Arguments > Sufficient/Necessary
On the GMAT, you must be able to identify any assumptions, or gaps, between the evidence and the conclusion. There are two types of Assumptions: Sufficient Assumptions and Necessary Assumptions. These questions typically ask you to identify the flaw and fix it. So, these are often like the Strengthening/Weakening questions we just discussed.
CHALLENGE: Identify the Necessary/Sufficient Assumptions
Necessary Assumption questions have stems phrased in the following ways:
- The argument requires/depends on/relies on the assumption that…
- Which of the following is an assumption on which the argument relies/depends?
- Which one of the following is an assumption the argument requires?
- The argument requires/depends on/relies on assuming which one of the following?
Sufficient Assumption questions are phrased like this:
- The conclusion follows logically if which one of the following is assumed?
- The conclusion of the argument can be properly drawn if which one of the following is assumed?
Notice that Necessary Assumption questions always contain a word that means “necessary” or “required”, while Sufficient Assumption questions ask for aguarantee that the conclusion will be reached.