Questions: Using logic to test a claim: Conditional statement, advanced
Your dentist gave you this statement as advice at your last visit.
If you don't brush your teeth twice a day and you don't floss every day, then you will get a cavity this year,
(a) Statements p, q, and r are defined as follows.
p: You brush your teeth twice a day,
q: You floss every day.
r: You get a cavity this year.
Write the dentist's statement in symbolic form using p, q, and r,
Symbolic form:
(b) Suppose the following situation occurs, You don't brush your teeth twice a day and you don't floss every day. And you don't get a cavity this year.
Based on this situation, complete the table to determine the truth of the dentist's statement.
Use T for true and F for false, You may add more columns to the table, but those added columns will not be graded.
Transcript text: Using logic to test a claim: Conditional statement, advanced
Your dentist gave you this statement as advice at your last visit.
If you don't brush your teeth twice a day and you don't floss every day, then you will get a cavity this year,
(a) Statements $p, q$, and $r$ are defined as follows.
p: You brush your teeth twice a day,
$q$ : You floss every day.
$r$ : You get a cavity this year.
Write the dentist's statement in symbolic form using $p, q$, and $r$,
Symbolic form: $\square$
(b) Suppose the following situation occurs, You don't brush your teeth twice a day and you don't floss every day. And you don't get a cavity this year.
Based on this situation, complete the table to determine the truth of the dentist's statement.
Use T for true and F for false, You may add more columns to the table, but those added columns will not be graded.
Solution
Solution Steps
Step 1: Define the Statements
\( p \): You brush your teeth twice a day.
\( q \): You floss every day.
\( r \): You get a cavity this year.
Step 2: Translate the Statement into Symbolic Form
The given statement is: "If you don’t brush your teeth twice a day and you don’t floss every day, then you will get a cavity this year."
In symbolic form, this can be written as:
\[ (\neg p \land \neg q) \rightarrow r \]
Step 3: Construct the Truth Table
Construct a truth table to determine the truth values of the statement \( (\neg p \land \neg q) \rightarrow r \).
| \( p \) | \( q \) | \( r \) | \( \neg p \) | \( \neg q \) | \( \neg p \land \neg q \) | \( (\neg p \land \neg q) \rightarrow r \) |
|--------|--------|--------|--------------|--------------|--------------------------|------------------------------------------|
| T | T | T | F | F | F | T |
| T | T | F | F | F | F | T |
| T | F | T | F | T | F | T |
| T | F | F | F | T | F | T |
| F | T | T | T | F | F | T |
| F | T | F | T | F | F | T |
| F | F | T | T | T | T | T |
| F | F | F | T | T | T | F |
Final Answer
The symbolic form of the dentist's statement is:
\[ (\neg p \land \neg q) \rightarrow r \]