I think it should be 50, really sorry if it wasn't multiplying.
Sum of two opposite angles in a Cyclic Quadiratral is 180°
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Answer:
The ratio of boys to girls is 4:5. So let 4x be the number of boys and 5x be the number of girls. Then 4x+5x = 9x is the total number of students. Then the fraction of boys in the class is 4x/9x = 4/9.
8 books will be on each shelf. There will be 4 shelves for the mystery books and 7 shelves for the biography books.
Sqrt(x^16) is x^8.
As you can see, x^8 * x^8 = x*x*x*x*x*x*x*x * x*x*x*x*x*x*x*x which equals x^16
I don't know why Cortesalondra28 deleted my answer to the question and sayid it was wrong..