How to buy hotel paper?

The most economical way: 1 box of 20 plus 5 boxes of 3 boxes, 60x1+5x10 =10.

The thinking process meets the requirements of 35 boxes of less money. Of the three ways, it is known that buying 1 box is the most expensive. Buy as few boxes as possible when you buy, or you won't pay the bill. List the combinations that can meet the conditions and get the results.

Full bill box: 35 x 4 = 140 yuan.

3 boxes 10 yuan single box combination:11x10+2x4 =118.

20 boxes of 3 boxes per box 10 yuan: 60x1+5x10 =1/kloc-0.