Use the tabulated data provided to determine the probability of the compound event below.

A triage nurse has kept track of patients' temperatures and whether or not they had infection or illness. The data is tabulated below.

[tex]\[
\begin{array}{lcc}
& \text{Had infection or illness} & \text{Did not have infection or illness} \\
\text{Temperature} \ \textgreater \ 100^{\circ} \text{F} & 44 & 11 \\
\text{Temperature} \leq 100^{\circ} \text{F} & 15 & 43 \\
\end{array}
\][/tex]

Find the probability of a patient having a temperature above [tex]$100^{\circ} \text{F}$[/tex] or having an infection/illness.

[tex]\[
P(A \text{ or } B) = \square
\][/tex]

(Round your answer to three decimal places)



Answer :

To determine the probability of a patient having a temperature above [tex]$100^{\circ} F$[/tex] or having an infection/illness, we need to analyze the given data step by step.

First, let's summarize the provided data:

- Patients with temperature > [tex]$100^{\circ} F$[/tex] and who had an infection/illness: [tex]\(44\)[/tex]
- Patients with temperature > [tex]$100^{\circ} F$[/tex] and who did not have an infection/illness: [tex]\(11\)[/tex]
- Patients with temperature [tex]\(\leq 100^{\circ} F\)[/tex] and who had an infection/illness: [tex]\(15\)[/tex]
- Patients with temperature [tex]\(\leq 100^{\circ} F\)[/tex] and who did not have an infection/illness: [tex]\(43\)[/tex]

Step 1: Calculate the total number of patients.

[tex]\[ \text{Total patients} = 44 + 11 + 15 + 43 = 113 \][/tex]

Step 2: Calculate the probability of having a temperature above [tex]$100^{\circ} F$[/tex] (Event A).

[tex]\[ P(\text{Temp} > 100^{\circ} F) = \frac{\text{Number of patients with temp > 100^{\circ} F}}{\text{Total patients}} \][/tex]
Where:
[tex]\[ \text{Number of patients with temp > 100^{\circ} F} = 44 + 11 = 55 \][/tex]

[tex]\[ P(\text{Temp} > 100^{\circ} F) = \frac{55}{113} = 0.487 \][/tex]

Step 3: Calculate the probability of having an infection/illness (Event B).

[tex]\[ P(\text{Infection/Illness}) = \frac{\text{Number of patients with infection/illness}}{\text{Total patients}} \][/tex]
Where:
[tex]\[ \text{Number of patients with infection/illness} = 44 + 15 = 59 \][/tex]

[tex]\[ P(\text{Infection/Illness}) = \frac{59}{113} = 0.522 \][/tex]

Step 4: Calculate the probability of having both a temperature above [tex]$100^{\circ} F$[/tex] and an infection/illness (Intersection of A and B).

[tex]\[ P(\text{Temp} > 100^{\circ} F \cap \text{Infection/Illness}) = \frac{\text{Number of patients with temp > 100^{\circ} F and infection/illness}}{\text{Total patients}} \][/tex]
Where:
[tex]\[ \text{Number of patients with temp > 100^{\circ} F and infection/illness} = 44 \][/tex]

[tex]\[ P(\text{Temp} > 100^{\circ} F \cap \text{Infection/Illness}) = \frac{44}{113} = 0.389 \][/tex]

Step 5: Calculate the probability of either having a temperature above [tex]$100^{\circ} F$[/tex] or having an infection/illness (Union of A and B).

Using the formula for the union of two events:
[tex]\[ P(A \cup B) = P(A) + P(B) - P(A \cap B) \][/tex]

[tex]\[ P(\text{Temp} > 100^{\circ} F \text{ or Infection/Illness}) = 0.487 + 0.522 - 0.389 = 0.619 \][/tex]

Therefore, the probability [tex]\( P(\text{Temp} > 100^{\circ} F \text{ or Infection/Illness}) \)[/tex] is [tex]\( \boxed{0.619} \)[/tex].