Add the students who choose the museum and the students who choose the factory to get 95. You would then need to divide the amount of students who choose the museum by the total amount of students. Your answer would be 0.6, or 60%
4 different streets with 5 customers on each means 4*5 customers or 20 customers. If he has 20 customers and he gets $10 from each one, thats 20*10. he collected $200