How many boards would i need to build a table 36 inches wide and my boards are 3.75 inches wide?

Aculture started with 3000 bacteria. after 5 hours it grew to 3900 bacteria. predict how many bacteria will be present after 9 hours

Can someone me out here and the tell me the greatest common factor

Richard save $32 in march he saved $48 in april and $38 in may then richard spent $113 on a keyboard how much money does richard have left