Help me please answer properly..

1. Sheila is 30 minutes late for variety show that is three hours long. What fraction of the variety show does he miss?

2. A basket has 120 bananas and mangoes. If there are 90 mangoes. What is the ratio of mangoes to bananas?
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1.A class of 32 students has 12 girls. What is the ratio of girls to boys?

2.what is 15 out 125 expressed as a fraction?

3.a class of 54 students 16 boys.
What is the ratio of boys to girls?
B. what is the ratio of boys to the entire class?