Recursive function f(7)=5.18

Combined megan and kelly worked 60 hours.kelly worked twice as many hours as megan.how many hours did they each worked?

News cameras take an overhead picture of a crowd at an outdoor event journalist then count the total number of people in the picture and use the sample of estimate the total number of people in the crowd this process is an example of

Acollection of coins has value of 64 cents. there are two more nickels than dimes and three times as many pennies as dimes in this collection. how many of each kind of coin are in the collection?