Rachel has 60 scones. She sells them to Robbie, Cameron, Lou's, Tom and Charlie in that order. Each customer buys more scones than the last and the increase is the same number in each case. Robbie and Cameron's combined total number of scones is three sevenths of the total of Louis, Tom and Charlie. How many scones does each boy buy?

Suppose robbie buys x scones then according to the question ... cameron will have x+y

... lou's will have (x+y) + y=x+2y ...

Tom=x+3y ...

Charlie=x+4y ...

now as we know that the combines scones of robbie and Cameron is 3/7 times of total of louis ...

x + (x+y) = 3/7 (x+3y+x+2y+x+4y) ... solve this ... and this will be your 1st equation ... and second equation will be x+x+2y+x+3y+x+4y=60 ... And solve both equation simultaneously and then you will have the answers of x and y the put the values of x and y in each of the equation that i have written above for each person