Speed getsa u brainle

Tom can paint the fence in 12 hours, but if he works together with a friend they can finish the job in 8 hours. how long would it take for his friend to paint this fence alone?

Jonathan can type 20 documents in 40 minutes ,and susan can type it in 30 minutes and jack can type it in 24 minutes working together ,how much time will it is take them type the same document

The coordinate grid shows a pentagon. the pentagon is translated 3 units to the right and 5 units up to create a new pentagon. what is the rule for the location of the new pentagon?