Question

select the correct answer from each drop - down menu.

based on the data in the two - way table, the probability of being 25 - 35 years old given a hemoglobin level above 11 is
the probability of being 25 - 35 years old is
being 25 - 35 years old and having a hemoglobin level above 11 dependent on each other.

hemoglobin level	age
----	----	----	----	----
	less than 25 years	25 - 35 years	above 35 years	total
less than 9	21	32	76	129
between 9 and 11	49	52	46	147
above 11	69	44	40	153
total	139	128	162	429

Explanation:

Step1: Recall conditional - probability formula

The formula for conditional probability is $P(A|B)=\frac{P(A\cap B)}{P(B)}$. Here, let $A$ be the event of being 25 - 35 years old and $B$ be the event of having a hemoglobin level above 11.
$P(A\cap B)=\frac{44}{429}$ (number of people 25 - 35 years old with hemoglobin above 11 divided by total number of people), $P(B)=\frac{153}{429}$ (number of people with hemoglobin above 11 divided by total number of people). Then $P(A|B)=\frac{\frac{44}{429}}{\frac{153}{429}}=\frac{44}{153}\approx0.288$.

Step2: Calculate probability of being 25 - 35 years old

The probability of being 25 - 35 years old, $P(A)=\frac{128}{429}\approx0.298$.

Step3: Check for dependence

Two events $A$ and $B$ are independent if $P(A|B) = P(A)$. Since $\frac{44}{153}
eq\frac{128}{429}$, the events are dependent.

Answer:

The probability of being 25 - 35 years old given a hemoglobin level above 11 is $\frac{44}{153}$.
The probability of being 25 - 35 years old is $\frac{128}{429}$.
Being 25 - 35 years old and having a hemoglobin level above 11 is dependent on each other.