How do you solve these? I guess I have to find how much they are in percents

During a bike challenge riders have to collect various colored ribbons each 1/2 mile they collect a red ribbon each eighth mile they collect a green ribbon and each quarter mile they collect a blue ribbion wich colors of ribion will be collected at the 3/4 markrer

Julius sold five times as many computers as sam sold last year. in total, they sold 78 computers. how many computers did julius sell?

Kendra had twice as much money as kareem. kendra later spent $8 and kareem earned $6. by then,the two had the same amount of money. how much money did each have originally?