In a collection of 80 books, 34 have leather covers and 18 were published before 1850. If 42 of these books were published after 1850 and do not have leather covers, how many books were published before 1850 and have leather covers?

Bruce is getting materials for a chemistry experiment his teacher gives him a container that has 0.25 liter of liquid in it.bruce need to use 0.4 of this liquid for the experiment. how much liquid will bruce use?

What is r i 4.5+10r=-6.5 with work pls

Solve the problem by making up an equation. a man could arrive on time for an appointment if he drove the car at 40 mph; however, since he left the house 15 minutes late, he drove the car at 50 mph and arrive 3 minutes early for the appointment. how far from his house was his appointment?