Question

a survey is given to 1,432 people about whether they take daily supplemental vitamins and whether they eat breakfast on a regular basis. the results are shown in the two - way table on the left. based on the survey results, what is the missing value in the relative frequency table (on the right) rounded to the nearest whole percent?
the two - way table (left) for counts:

	breakfast	no breakfast
no daily vitamin	476	304

the relative frequency table (right) with some values:

	breakfast	no breakfast
no daily vitamin	33%	(missing)

the multiple - choice options are:
a 53%
b 27%
c 21%
d 20%

Explanation:

Step1: Identify the number of people with no daily vitamin and no breakfast

From the two - way table, the number of people with no daily vitamin and no breakfast is 304.

Step2: Calculate the relative frequency

The total number of people surveyed is 1432. The formula for relative frequency is $\text{Relative Frequency}=\frac{\text{Number of people in the category}}{\text{Total number of people}}\times100\%$.
So, the relative frequency for the category "No daily vitamin" and "No breakfast" is $\frac{304}{1432}\times 100\%$.
First, calculate $\frac{304}{1432}\approx0.2123$. Then multiply by 100% to get $0.2123\times100\% = 21.23\%\approx21\%$.

Answer:

21% (Option C)