In a school 70% of the students are girls.The number of boys are 510.Then the total number of students in the school is:

Options

A. 850
B. 1700
C. 1830
D. 1900

Answer

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

1. **Understand the given information**: We know that 70% of the students are girls, and the number of boys is 510. This means that the remaining percentage of students (100% - 70%) are boys, which is 30%.

2. **Set up the relationship**: Since 30% of the total number of students represents the boys, we can denote the total number of students as \( T \). Therefore, we can write the equation:
\[ 30\% \text{ of } T = 510 \]

3. **Convert percentage to decimal**: To solve for \( T \), we convert 30% to a decimal:
\[ 30\% = \frac{30}{100} = 0.3 \]
So, we can rewrite the equation as:
\[ 0.3T = 510 \]

4. **Solve for \( T \)**: To find \( T \), we divide both sides of the equation by 0.3:
\[ T = \frac{510}{0.3} \]

5. **Calculate the total**: Performing the division:
\[ T = 510 \div 0.3 = 1700 \]

6. **Conclusion**: Therefore, the total number of students in the school is \( 1700 \).

### Summary of the Steps:
1. Identify the percentage of boys.
2. Set up the equation relating boys to total students.
3. Convert percentage to decimal.
4. Solve for total students.
5. Calculate the total.