Question

5.4.3 quiz: two-way frequency tables
a medical company tested a new drug on 100 people for possible side
effects. this table shows the results.

	side effects	no side effects	total
children	21	29	50
total	27	73	100

compare the probability that an adult has side effects with the probability
that a child has side effects. draw a conclusion based on your results.

○ a. ( p(\text{side effects}|\text{child}) = 0.21 )
( p(\text{side effects}|\text{adult}) = 0.60 )

conclusion: children have a much greater chance of having side
effects than adults.

○ b. ( p(\text{side effects}|\text{child}) = 0.42 )
( p(\text{side effects}|\text{adult}) = 0.12 )

conclusion: children have a much greater chance of having side
effects than adults.

○ c. ( p(\text{side effects}|\text{child}) = 0.21 )
( p(\text{side effects}|\text{adult}) = 0.60 )

conclusion: children have a much lower chance of having side

Explanation:

Answer:

B. \( P(\text{side effects|child}) = 0.42 \), \( P(\text{side effects|adult}) = 0.12 \); Conclusion: Children have a much greater chance of having side effects than adults.

(Calculation: \( P(\text{side effects|child}) = \frac{21}{50} = 0.42 \), \( P(\text{side effects|adult}) = \frac{6}{50} = 0.12 \). Since \( 0.42 > 0.12 \), children have a greater chance.)