On Sunday, my parents and I went to the supermarket to buy toothpaste. We found that there are two ways to sell the same kind of bamboo salt toothpaste: 1, three pieces110g toothpaste, fresh and pleasant package 17.9 yuan; 2. A toothpaste 8 yuan with a weight of 150g. Which of these two ways do you think saves money? "Now I'm stumped. My mother said to me," Today, let's put 17.9 yuan pawn 18 yuan. Do the math! " I immediately said, "Save money by buying fresh and enjoyable clothes." Mother asked, "Why? "I said I thought so: three boxes 18 yuan, each box of toothpaste 6 yuan 18 ÷ 3 = 6 (yuan). 150g toothpaste per box of 8 yuan, that is, more 2 yuan money to buy 40g toothpaste, so 1 yuan can buy 20g toothpaste. And if you buy 150g toothpaste, 1 yuan can't buy 20g. So I think buying fresh and pleasant clothes saves money! Hearing this, my mother said to me happily, "Great! Learning math well is really useful! "