In a class the girls are 60 % of the total number of students and the boys are 18 in number . How many students are there in the class ?

Options

A. `35`
B. `25`
C. `45`
D. `55`

Answer

To find the total number of students in the class, we can follow these steps:

### Step 1: Define the total number of students
Let the total number of students in the class be represented by \( X \).

### Step 2: Determine the percentage of boys
Since girls make up 60% of the total students, the percentage of boys in the class is:
\[ 100\% - 60\% = 40\% \]

### Step 3: Set up the equation
We know that the number of boys is 18. Since boys represent 40% of the total students, we can express this as:
\[ 40\% \text{ of } X = 18 \]
This can be written mathematically as:
\[ \frac{40}{100} \times X = 18 \]

### Step 4: Solve for \( X \)
To isolate \( X \), we can rearrange the equation:
\[ X = \frac{18 \times 100}{40} \]

### Step 5: Calculate \( X \)
Now, we can perform the calculations:
\[ X = \frac{1800}{40} = 45 \]

### Conclusion
The total number of students in the class is \( 45 \).

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