The ratio of girls to boys in the school is 3 to 1.If there is a total of 400 students, how many are boys? The answer must be a whole number.
To find the number of boys, we first need to find the total number of girls.
Since the ratio of girls to boys is 3 to 1, the total ratio can be written as 3 + 1 = 4.
Let x be the number of girls. Therefore, the number of boys is 400 - x.
Since the ratio of girls to boys is 3 to 1, we can write the equation:
x / (400 - x) = 3 / 1.
By cross-multiplying, we get:
x = 3(400 - x).
Expanding the equation, we have:
x = 1200 - 3x.
Adding 3x to both sides of the equation, we get:
4x = 1200.
Dividing both sides by 4, we find:
x = 300.
Therefore, there are 300 girls in the school. And since the total number of students is 400, the number of boys is 400 - 300 = 100.
So, there are 100 boys in the school.