Lee surveyed students at school about whether they buy lunch or bring lunch from home. The data she gathered is shown in the two-way table below.
Source of Student Lunches
| | Bring Lunch to School | Buy Lunch in the Cafeteria |
|---|---|---|
| Boys | 12 | 18 |
| Girls | 20 | 30 |
According to the data in the table, what percentage of boys bring lunch to school?
A. 15%
B. 37.5%
C. 40%
D. 66.7%
Answer (2)
40% of boys bring lunch to school, as calculated by dividing the number of boys who bring lunch (12) by the total number of boys (30) and multiplying by 100. The correct choice is C. 40%.
;
Calculate the total number of boys: 12 + 18 = 30 .
Calculate the fraction of boys who bring lunch: 30 12 .
Simplify the fraction: 30 12 = 5 2 .
Convert the fraction to a percentage: 5 2 × 100 = 40% .
Explanation
Analyze the data First, let's analyze the data provided in the table. We are given the number of boys who bring lunch (12) and the number of boys who buy lunch (18). We need to find the percentage of boys who bring lunch to school.
Calculate the total number of boys To find the percentage, we first need to calculate the total number of boys. We add the number of boys who bring lunch and the number of boys who buy lunch: T o t a l B oys = 12 + 18 = 30
Calculate the percentage Now, we calculate the percentage of boys who bring lunch to school. We divide the number of boys who bring lunch by the total number of boys and multiply by 100: P erce n t a g e = 30 12 × 100
Simplify and calculate the final percentage Let's simplify the fraction before multiplying by 100: 30 12 = 5 2 Now, multiply by 100: P erce n t a g e = 5 2 × 100 = 40
State the final answer Therefore, 40% of boys bring lunch to school.
Examples
Understanding percentages is very useful in everyday life. For example, if you want to know what percentage of your class prefers a certain sport, you can use the same method. Collect the data, divide the number of students who prefer the sport by the total number of students, and multiply by 100 to get the percentage. This helps in making informed decisions, like planning activities that most students will enjoy. Percentages are also used to calculate discounts while shopping, analyze survey results, and understand statistical data.
