We know that there are 16 girls. That is the first part of the ratio. Now, it says girls to students, which mean you have to add up the total of girls and boys together. 12+16=28. There are 28 students in total. Now, you have the ratio of 16:28. But, it says simplified...so we need to divide both sides of the ratio by a number. Let's choose 4 because 4 can go both into 16 and 28. 16/4=4. 28/4=7. So, the simplified ratio of girls to students in the classroom is 4:7.
The radius is the distance from the center to a point anywhere along the edge of the circle. To find the distance between these two points, use the distance formula.
