Today, my mother and I went shopping in the supermarket. There are a sea of people in the supermarket, and the goods are dazzling. Mom quickly took me to buy what I needed at home. We bought a watermelon first. This watermelon is 3 yuan and weighs 4 Jin. Then we came to the place where meat was sold. 8 yuan bought a kilo of meat, but we bought three kilos. Then we bought another box of milk. A box of milk contains 16 boxes, and each box contains 3 yuan. Finally, we went to buy cookies and spent 15 yuan. When I was waiting in line to check out, my mother said to me, how much do you want to pay first? I thought about it, watermelon 3*4= 12 yuan, meat 8*3=24 yuan, milk 16*3=48 yuan, take 12 and add 48 first, which is just 60 yuan, and then 24 yuan equals 84 yuan. Oh, and biscuits, 84+/kloc-0. I asked my mother to prepare a 100 yuan to pay. When we checked out, the assistant's aunt was like me, and it was 99 yuan after calculation. My mother praised me for being clever. I said to my mother, then you should invite me next time you buy something!

This shopping is really rewarding. Not only do you know the prices of some daily necessities, but you will also use the mathematics knowledge you usually learn. It turns out that mathematics is around us.

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Today, my father gave me 50 yuan to go shopping, and I went to the supermarket. I looked at something, hey! Isn't that "a lot of fish" "Lots of fish" is my favorite. I went over and bought five boxes of "Duoduo Fish".

Then I went to give money, and my aunt asked me, "How much do you calculate?" Then thinking of math, my aunt said, "A lot of fish, 4 yuan a box." Then I did the math. 4*5=20 (yuan). Later, I gave my aunt 50 yuan. My aunt said, "Little friend, how much do you want from my aunt?" 50‐20=30 (yuan) Oh, auntie, you want to find 30 yuan for me, right? My aunt gave me change for 30 yuan and said, "You are so smart, little friend."

I bought "a lot of fish" with 50 yuan, and solved the practical problems in our life with mathematical knowledge. The mathematical knowledge of two-step calculation is clear. I hope you can carry forward, persevere and study mathematics more practically.