Tim would spend 88 dollars on cups and plates becaus since 12x5 is 60 and 10x6 is 60 then that gets you to the same amount of cups and plates. so you would add 3 plus 5 together to get 8 and then 6 plus 5 togeher to get 11 and then you muliply those toether to get how mcuh he would ahve to spend.
Hope this helps :)