I remember one day, I was tired of playing with my lovely dog Niu Niu at home, so I picked up Niu Niu and watched TV. After a few steps, I felt that Niu Niu was so heavy, and I thought, how heavy is Niu Niu? As soon as I thought about it, I immediately put Niu Niu on the weighing scale, but this naughty guy always moves around, and weighing scale's pointer swings from side to side, alas! I have to think of a way. Suddenly I had an epiphany, and the plan came. I picked Niu Niu up and weighed it together, and the pointer stopped at 55. I put Niu Niu down again and weighed 50 kilograms myself. In this way, the total weight of Niu Niu and I is 55 kg, MINUS my weight of 50 kg, I know that Niu Niu's weight is 5 kg, which is also 10 kg.
Another time, my mother and I went shopping and saw a hat exactly like my father's hat on a shelf, with a "20% discount" sign hanging next to it. I asked my mother, "What does 20% discount mean?" Mom told me that the 20% discount is the original price multiplied by 0.8. I asked my mother again, "Is this the discount?" Mom nodded. I immediately said, "Mom, I like this hat very much. Can you buy me one too? " Mother thought for a moment and said, "well, this is a test for you." This hat is 20% off now, and then 10% off with the membership card. How much do we have to pay? " What is the discount? "I immediately used my brain and silently thought: There are two discounts. The discount of the membership card is calculated according to the price after the first discount, not the original price. First, it should be 98× 0.8 = 78.4. Before, my mother said that after shopping in the mall, all discounts were rounded off, and then 78× 0.9 = 70.2. So this hat is now in 70 yuan, and the original price of 98 yuan is reduced by the current price of 70 yuan, and the discount is given to 28 yuan. I told my mother the answer excitedly. My mother smiled and said, "by the way, this hat is yours now." "I happily picked up my hat and put it on my head, feeling flattered.
I found that mathematics is actually everywhere. As long as we are good at discovering, observing and thinking, the ocean of mathematics will make us soar!