Statements, and, or, not and if…then
Decide which sentences are statements, use and, or and not correctly, test a promise "if … then …" and find the contrapositive.
- France: grade 11
- Germany: grade 5
- Iran: grade 11
- Afghanistan: grade 10
- Palestine: grade 11
- Ukraine: grade 7
- Russia: grade 7
Guide
A statement is a sentence that is either true or false. "7 is even" is a statement (a false one); "x + 2 = 5" and "Close the door" are not.
"p and q" is true only when both parts are true. "p or q" is true when at least one part is true. "not p" turns true into false.
"If p then q" is false only when p is true and q is false. Its contrapositive "if not q then not p" always says the same thing. Its converse "if q then p" and inverse "if not p then not q" may not.