Question

fill in the blank 50 points
an optometrist surveyed a school with 484 students collected information about how many of the students wear glasses. complete the table.

	always wears glasses	sometimes wears glasses	never wears glasses	total
girls	36	55	144	235
total	76	103	305	484

what is the relative frequency of students who are boys who sometimes wear glasses? round to the nearest percent.
type your answer...
what percentage of girls never wear glasses? round to the nearest percent.
type your answer...
what percentage of students are boys? round to the nearest percent.
type your answer...
what percentage of students always wear glasses? round to the nearest percent.
type your answer...

Explanation:

First Sub - Question: Relative Frequency of Boys Who Sometimes Wear Glasses

Step1: Recall Relative Frequency Formula

Relative frequency of an event is the number of times the event occurs divided by the total number of observations. Here, the number of boys who sometimes wear glasses is 48, and the total number of students is 484.
So the formula is $\text{Relative Frequency}=\frac{\text{Number of boys who sometimes wear glasses}}{\text{Total number of students}}=\frac{48}{484}$.

Step2: Calculate and Round

$\frac{48}{484}\approx0.0992$. To convert to a percentage, multiply by 100: $0.0992\times100 = 9.92\%\approx10\%$.

Step1: Identify the Numbers

The number of girls who never wear glasses is 144, and the total number of girls is 235. The formula for percentage is $\text{Percentage}=\frac{\text{Number of girls who never wear glasses}}{\text{Total number of girls}}\times100=\frac{144}{235}\times100$.

Step2: Calculate and Round

$\frac{144}{235}\approx0.6128$. Multiply by 100: $0.6128\times100 = 61.28\%\approx61\%$.

Step1: Identify the Numbers

The number of boys is 249, and the total number of students is 484. The formula is $\text{Percentage}=\frac{\text{Number of boys}}{\text{Total number of students}}\times100=\frac{249}{484}\times100$.

Step2: Calculate and Round

$\frac{249}{484}\approx0.5145$. Multiply by 100: $0.5145\times100 = 51.45\%\approx51\%$.

Answer:

10%

Second Sub - Question: Percentage of Girls Who Never Wear Glasses