136
Statements: true or false
Textbook: Part 4, lesson 136, pp. 81–83
GoalThe idea of a statement; telling true statements from false ones.
New words
statement · mulohazatrue · rostfalse · yolg‘ondeclarative sentence · darak gap
Explanation
A declarative sentence that can be clearly said to be true or false is called a statement. A correct statement is true; an incorrect one is false. Questions and exclamations are not statements. To check a mathematical statement we calculate: “8 × 5 = 40” is true, “9 + 6 = 14” is false.
Worked examples
“A week has 8 days” is a false statement. “A day has 24 hours” is a true statement.
“Is the weather good today?” is a question and “What a lovely spring!” is an exclamation. Neither is a statement.
Class activity
“Green and red card”: the teacher says a sentence. Children raise a green card if it is true and a red card if it is false. If it is not a statement, no card is raised.
Practice
1
Is the statement “7 × 8 = 54” true or false?
False, because 7 × 8 = 56.
2
Is the statement “345 is a multiple of 5” true or false?
True: 345 = 5 × 69.
3
Check the statement “54 000 : 36 = 1 400” by calculating.
False, because 54 000 : 36 = 1 500.
4
Which sentence is not a statement: “A year has 12 months” or “Which grade are you in?”
“Which grade are you in?” – it is a question.
5
Turn the false statement “9 + 6 = 14” into a true one.
9 + 6 = 15