Grade 12 · Reading & language
Distinguish necessary and sufficient conditions practice
Use the exact direction of a stated rule to distinguish a guarantee from a requirement, without reversing an implication.
Opening your practice adventure…
Try a sample
READ THE PASSAGE
A model says a signal is accepted exactly when tests A and B both succeed. A succeeds but B fails.
What follows within this model?
- The signal is accepted because one test succeeds.
- Every signal fails both tests.
- The signal is not accepted.
- The two tests are irrelevant.
See the answer & why
The signal is not accepted.
Exactly when defines the joint requirement; one success does not satisfy both tests.
A little hint: If A then B guarantees B when A holds; B only if A makes A required. Do not silently turn either rule into an equivalence.
A teaching tip
If A then B guarantees B when A holds; B only if A makes A required. Do not silently turn either rule into an equivalence.