First, figure out the cost of the items with tax; for Tommy we have 20*0.08 = 1.6, add that 1.6 to the 20 and his purchase is $21.6, for John we have 25*0.08 = 2, add 2 to his 25 and his purchase is $27. To find the difference we subtract 27-21.6 = 5.4 or $5.40
Billy would have of scored a total of 40 points because then you split 90 in half you get 40 50 and then 50 is 10 more than 40 and logan scored 10 more so here is your answer
