Someome please help me

Explain how you can find the missing fraction in 3 4/5 / (blank) 2 5/7. then find the missing fraction.

:24% of students in a class are girls. if there are less than 30 students in this class, how many students are there? how many girls are there?

Ascientist has 50 grams of a radioactive element. the amount of radioactive element remaining after t days can be determined using the equation (1) after two days the scientist receives a second shipment of 50 grams of the same element. the equation used to represent the amount of shipment 2 remaining after t days is 10) - 50 which of the following is an equivalent form of the expression for the amount remaining in shipment 2? what’s the answer?