Question

The ratio of boys to girls in a class is 7 to 3. Among the options below, an acceptable value for the total number of students in the class is:

• A. 21
• B. 37
• C. 50
• D. 73

Hint:

To check ratio-based questions, always ensure the total number is a multiple of the sum of the ratio parts.

Answer 1

The Correct Option is C

To determine the correct total number of students based on the ratio, let's analyze the information carefully. The ratio of boys to girls is given as \(7 : 3\). 
 

Step 1: Understanding the ratio. 
A ratio of \(7 : 3\) means that out of every 10 students, 7 are boys and 3 are girls. Therefore, the total number of students must be a multiple of 10. 
 

Step 2: Verify each option. 
We now check the options to see which one is divisible by 10: \[ 21 \div 10 \text{ (not integer)} \\ 37 \div 10 \text{ (not integer)} \\ 50 \div 10 = 5 \text{ (integer)} \\ 73 \div 10 \text{ (not integer)} \] Only 50 is divisible by 10. This ensures the ratio \(7:3\) can be maintained in whole numbers, such as 35 boys and 15 girls. 
 

Step 3: Conclusion. 
Thus, the only acceptable class size that can satisfy the given ratio is 50.