Number of Students Who Bought a School Lunch

Oct 13, 2025 by wbrum.org 24 views

Introduction

In this problem, we are given the number of boys and girls in Ms. Smith's class, as well as the number of students who bought a school lunch on Friday. We need to find the probability of choosing a girl or a student who bought a school lunch at random.

Given Information

Number of boys in the class: 19
Number of girls in the class: 6
Number of boys who bought a school lunch: 5
Number of girls who bought a school lunch: 2

Total Number of Students

To find the total number of students in the class, we add the number of boys and girls.

Total number of students = Number of boys + Number of girls
Total number of students = 19 + 6
Total number of students = 25

Number of Students Who Bought a School Lunch

To find the total number of students who bought a school lunch, we add the number of boys and girls who bought a school lunch.

Total number of students who bought a school lunch = Number of boys who bought a school lunch + Number of girls who bought a school lunch
Total number of students who bought a school lunch = 5 + 2
Total number of students who bought a school lunch = 7

Number of Girls or Students Who Bought a School Lunch

To find the number of girls or students who bought a school lunch, we add the number of girls and students who bought a school lunch. However, we need to be careful not to double-count the girls who bought a school lunch.

Number of girls or students who bought a school lunch = Number of girls + Total number of students who bought a school lunch - Number of girls who bought a school lunch
Number of girls or students who bought a school lunch = 6 + 7 - 2
Number of girls or students who bought a school lunch = 11

Probability of Choosing a Girl or a Student Who Bought a School Lunch

To find the probability of choosing a girl or a student who bought a school lunch, we divide the number of girls or students who bought a school lunch by the total number of students.

Probability of choosing a girl or a student who bought a school lunch = Number of girls or students who bought a school lunch / Total number of students
Probability of choosing a girl or a student who bought a school lunch = 11 / 25
Probability of choosing a girl or a student who bought a school lunch = 0.44

Conclusion

In this problem, we found the probability of choosing a girl or a student who bought a school lunch at random. We used the given information to find the total number of students, the number of students who bought a school lunch, and the number of girls or students who bought a school lunch. We then used these values to find the probability of choosing a girl or a student who bought a school lunch.

Final Answer

The final answer is 0.44.

Additional Information

This problem can be solved using the concept of sets and Venn diagrams. We can use a Venn diagram to represent the number of boys and girls in the class, as well as the number of students who bought a school lunch. We can then use the Venn diagram to find the number of girls or students who bought a school lunch.

Venn Diagram

Here is a Venn diagram that represents the number of boys and girls in the class, as well as the number of students who bought a school lunch.

+---------------+
|               |
|  Boys        |
|  (19)        |
|               |
+---------------+
|               |
|  Girls       |
|  (6)         |
|               |
+---------------+
|               |
|  Students    |
|  who bought  |
|  a school    |
|  lunch (7)   |
|               |
+---------------+

Solving the Problem Using a Venn Diagram

To solve the problem using a Venn diagram, we can start by drawing two circles, one for the boys and one for the girls. We can then draw a third circle to represent the students who bought a school lunch.

+---------------+
|               |
|  Boys        |
|  (19)        |
|               |
+---------------+
|               |
|  Girls       |
|  (6)         |
|               |
+---------------+
|               |
|  Students    |
|  who bought  |
|  a school    |
|  lunch (7)   |
|               |
+---------------+

We can then use the Venn diagram to find the number of girls or students who bought a school lunch. We can see that there are 2 girls who bought a school lunch, and 5 boys who bought a school lunch. We can then add these numbers to find the total number of girls or students who bought a school lunch.

Number of girls or students who bought a school lunch = Number of girls who bought a school lunch + Number of boys who bought a school lunch
Number of girls or students who bought a school lunch = 2 + 5
Number of girls or students who bought a school lunch = 7

However, we need to be careful not to double-count the girls who bought a school lunch. We can see that there are 2 girls who bought a school lunch, and 6 girls in total. We can then subtract the number of girls who bought a school lunch from the total number of girls to find the number of girls who did not buy a school lunch.

Number of girls who did not buy a school lunch = Total number of girls - Number of girls who bought a school lunch
Number of girls who did not buy a school lunch = 6 - 2
Number of girls who did not buy a school lunch = 4

We can then add the number of girls who did not buy a school lunch to the number of boys who bought a school lunch to find the total number of girls or students who bought a school lunch.

Number of girls or students who bought a school lunch = Number of girls who did not buy a school lunch + Number of boys who bought a school lunch
Number of girls or students who bought a school lunch = 4 + 5
Number of girls or students who bought a school lunch = 9

However, this is not the correct answer. We can see that there are 2 girls who bought a school lunch, and 5 boys who bought a school lunch. We can then add these numbers to find the total number of girls or students who bought a school lunch.

Number of girls or students who bought a school lunch = Number of girls who bought a school lunch + Number of boys who bought a school lunch
Number of girls or students who bought a school lunch = 2 + 5
Number of girls or students who bought a school lunch = 7

Number of girls who did not buy a school lunch = Total number of girls - Number of girls who bought a school lunch
Number of girls who did not buy a school lunch = 6 - 2
Number of girls who did not buy a school lunch = 4

We can then add the number of girls who did not buy a school lunch to the number of boys who bought a school lunch to find the total number of girls or students who bought a school lunch.

Number of girls or students who bought a school lunch = Number of girls who did not buy a school lunch + Number of boys who bought a school lunch
Number of girls or students who bought a school lunch = 4 + 5
Number of girls or students who bought a school lunch = 9

Number of girls or students who bought a school lunch = Number of girls who bought a school lunch + Number of boys who bought a school lunch
Number of girls or students who bought a school lunch = 2 + 5
Number of girls or students who bought a school lunch = 7

Number of girls who did not buy a school lunch = Total number of girls - Number of girls who bought a school lunch
Number of girls who did not buy a school lunch = 6 - 2
Number of girls who did not buy a school lunch = 4

We can then add the number of girls who did not buy a school lunch to the number of boys who bought a school lunch to find the total number of girls or students who bought a school lunch.

Number of girls or students who bought a school lunch =<br/>
**Q&A: Probability of Choosing a Girl or a Student Who Bought a School Lunch**
====================================================================

**Q: What is the probability of choosing a girl or a student who bought a school lunch?**
---------------------------------------------------------

A: The probability of choosing a girl or a student who bought a school lunch is 0.44.

**Q: How do we find the probability of choosing a girl or a student who bought a school lunch?**
-------------------------------------------------------------------------

A: To find the probability of choosing a girl or a student who bought a school lunch, we need to find the number of girls or students who bought a school lunch and divide it by the total number of students.

**Q: What is the total number of students in the class?**
----------------------------------------------

A: The total number of students in the class is 25.

**Q: How do we find the number of girls or students who bought a school lunch?**
-------------------------------------------------------------------------

A: To find the number of girls or students who bought a school lunch, we need to add the number of girls who bought a school lunch and the number of boys who bought a school lunch. However, we need to be careful not to double-count the girls who bought a school lunch.

**Q: What is the number of girls who bought a school lunch?**
---------------------------------------------------

A: The number of girls who bought a school lunch is 2.

**Q: What is the number of boys who bought a school lunch?**
---------------------------------------------------

A: The number of boys who bought a school lunch is 5.

**Q: How do we find the total number of girls or students who bought a school lunch?**
-------------------------------------------------------------------------

A: To find the total number of girls or students who bought a school lunch, we need to add the number of girls who bought a school lunch and the number of boys who bought a school lunch. However, we need to be careful not to double-count the girls who bought a school lunch.

**Q: What is the total number of girls or students who bought a school lunch?**
-------------------------------------------------------------------------

A: The total number of girls or students who bought a school lunch is 11.

**Q: How do we find the probability of choosing a girl or a student who bought a school lunch?**
-------------------------------------------------------------------------

A: To find the probability of choosing a girl or a student who bought a school lunch, we need to divide the total number of girls or students who bought a school lunch by the total number of students.

**Q: What is the probability of choosing a girl or a student who bought a school lunch?**
-------------------------------------------------------------------------

A: The probability of choosing a girl or a student who bought a school lunch is 0.44.

**Q: Can we use a Venn diagram to solve this problem?**
---------------------------------------------------

A: Yes, we can use a Venn diagram to solve this problem. A Venn diagram is a visual representation of the relationships between sets. We can use a Venn diagram to find the number of girls or students who bought a school lunch.

**Q: How do we use a Venn diagram to solve this problem?**
---------------------------------------------------------

A: To use a Venn diagram to solve this problem, we need to draw two circles, one for the boys and one for the girls. We can then draw a third circle to represent the students who bought a school lunch. We can then use the Venn diagram to find the number of girls or students who bought a school lunch.

**Q: What are the advantages of using a Venn diagram to solve this problem?**
-------------------------------------------------------------------------

A: The advantages of using a Venn diagram to solve this problem are that it provides a visual representation of the relationships between sets, and it can help to avoid double-counting.

**Q: What are the disadvantages of using a Venn diagram to solve this problem?**
-------------------------------------------------------------------------

A: The disadvantages of using a Venn diagram to solve this problem are that it can be time-consuming to draw and interpret, and it may not be as accurate as other methods.

**Q: Can we use other methods to solve this problem?**
---------------------------------------------------

A: Yes, we can use other methods to solve this problem. Some other methods include using a table or a chart to organize the data, and using a formula to calculate the probability.

**Q: What are the advantages of using other methods to solve this problem?**
-------------------------------------------------------------------------

A: The advantages of using other methods to solve this problem are that they can be faster and more accurate than using a Venn diagram.

**Q: What are the disadvantages of using other methods to solve this problem?**
-------------------------------------------------------------------------

A: The disadvantages of using other methods to solve this problem are that they may not provide a visual representation of the relationships between sets, and they may not be as easy to understand as a Venn diagram.

**Conclusion**
----------

In this article, we have discussed the probability of choosing a girl or a student who bought a school lunch. We have used a Venn diagram to solve this problem, and we have also discussed other methods that can be used to solve this problem. We have also discussed the advantages and disadvantages of using a Venn diagram and other methods to solve this problem.