To calculate the attack rate for each food item using 250 as a constant denominator, we use the formula:

Question

ScanSolve AI Tutor · Accepted Answer

To calculate the attack rate for each food item using 250 as a constant denominator, we use the formula:

\text{Attack Rate} = \frac{\text{Number of people who ate a specific food and got sick}}{\text{Total number of attendees (constant)}} \times 100\%

1. Attack Rate for Rice

Identify the number of people who ate rice and had diarrhea.
Number of people who ate rice and had diarrhea = 12
Use the constant total number of attendees.
Total attendees = 250
Calculate the attack rate for rice.
$\text{Attack Rate (Rice)} = \frac{12}{250} \times 100\%$ $\text{Attack Rate (Rice)} = 0.048 \times 100\%$ $\text{Attack Rate (Rice)} = 4.8\%$
The attack rate for rice is $\boxed{\text{4.8\%}}$ .

2. Attack Rate for Swallow
Identify the number of people who ate swallow and had diarrhea.
Number of people who ate swallow and had diarrhea = 17
Use the constant total number of attendees.
Total attendees = 250
Calculate the attack rate for swallow.
$\text{Attack Rate (Swallow)} = \frac{17}{250} \times 100\%$ $\text{Attack Rate (Swallow)} = 0.068 \times 100\%$ $\text{Attack Rate (Swallow)} = 6.8\%$
The attack rate for swallow is $\boxed{\text{6.8\%}}$ .

3. Attack Rate for Beans Porridge
Identify the number of people who ate beans porridge and had diarrhea.
Number of people who ate beans porridge and had diarrhea = 7
Use the constant total number of attendees.
Total attendees = 250
Calculate the attack rate for beans porridge.
$\text{Attack Rate (Beans Porridge)} = \frac{7}{250} \times 100\%$ $\text{Attack Rate (Beans Porridge)} = 0.028 \times 100\%$ $\text{Attack Rate (Beans Porridge)} = 2.8\%$
The attack rate for beans porridge is $\boxed{\text{2.8\%}}$ .

Step-by-step solution