Can anyone help with this?

To complete your spring schedule, you must add calculus and physics. at 9: 30, there are three calculus sections and two physics sections; while at 11: 30, there are two calculus sections and three physics sections. how many ways can you complete your schedule if your only open periods are 9: 30 and 11: 30?

You eat 8 strawberries and your friend eats 12 strawberries from a bowl. there are 20 strawberries left. which equation and solution give the original number of strawberries?

Hiroaki wants to find 3 3/4 - 7/8 explain why he must rename 3 3/4 to do the subtraction.