There are 10 doors to a coliseum. In how many ways can a person go in and out if one can enter any door but leave using another door?.

Arecycling company gives you 5 cents for every plastic bottle and 10 cents for every glass bottle. from a certain individual the recycling company received 59 bottles and paid $4.55. how many glass bottles did the individuals recycle?

Rick is on a bicycle trip. every 4 days he bikes 230 km. if rick keeps this same pace for 16 days, how many kilometers will he bike?

How do we determine if they are made with matter