L=U²A divided by (A+B)² make A the subject of formular

Determine the number of girls in a math class with 87 boys if there are 25 girls for every 75 boys

Last year, a state university received 3,560 applications from boys. of those applications, 35 percent were from boys who lived in other states. part a)how many applications did the university receive from boys who lived in other states? part b)applications to the university from boys represented 40percent of all applications. how many applications did the university receive in all? i don't how to do part b so me and plz tell how you got your answer

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