11 plus what number equals 16 in order to complete your problem.
You can use the CPCTC (Corresponding Parts of Congruent Triangles are Congruent) property. This means that when two triangles are congruent, all the corresponding parts are congruent to each other.
Have an awesome day! :)
You could understand the ration as parts: the total number of parts was 3+7=10.
So girls were 3/10 parts and boys 7/10 parts. The difference was 7-3=4 parts. this difference is equal to 360, so each part is 90 (4*90 =360).
so girls are "3 parts" and each part is 90, then the number of girls is 3*90=270.