Given:
The two way table.
To find:
The conditional probability of P(Drive to school | Senior).
Solution:
The conditional probability is defined as:
![P(A|B)=(P(A\cap B))/(P(B))](https://img.qammunity.org/2022/formulas/mathematics/high-school/dgjg3lvbhs5682gwk10g53pm7q27drhpzw.png)
Using this formula, we get
...(i)
From the given two way table, we get
Drive to school and senior = 25
Senior = 25+5+5
= 35
Total = 2+25+3+13+20+2+25+5+5
= 100
Now,
![P(\text{Drive to school and senior})=(25)/(100)](https://img.qammunity.org/2022/formulas/mathematics/high-school/10z6913j17dkkeg0zetw38bp7ejpmwd3to.png)
![P(\text{Senior})=(35)/(100)](https://img.qammunity.org/2022/formulas/mathematics/high-school/wi6spg71932yniqbawyqxkac60g5ksge6c.png)
Substituting these values in (i), we get
![P(\text{Drive to school }|\text{ Senior})=((25)/(100))/((35)/(100))](https://img.qammunity.org/2022/formulas/mathematics/high-school/y74vmkmqduqxq31a9vnrf3rbgj7espiyo4.png)
![P(\text{Drive to school }|\text{ Senior})=(25)/(35)](https://img.qammunity.org/2022/formulas/mathematics/high-school/b1oi9z212xo3ezm3ydg4bkidp2ulg98yod.png)
![P(\text{Drive to school }|\text{ Senior})=0.7142857](https://img.qammunity.org/2022/formulas/mathematics/high-school/dpsctfnuggeeq7kv15utvrdotsvpblsuc9.png)
![P(\text{Drive to school }|\text{ Senior})\approx 0.71](https://img.qammunity.org/2022/formulas/mathematics/high-school/1cxydtzzdk3kf195av6t541q8eqaikucpm.png)
Therefore, the required conditional probability is 0.71.