When it comes to circles, I think of the center, radius and diameter. The knowledge of the center of the circle is: when drawing a circle, the fixed point is called the center of the circle and is represented by the letter O; The knowledge point of radius is: the line segment connecting the center of the circle and any point on the circle is called radius, and the knowledge point of using the letter R to represent the diameter is: the line segment passing through the center of the circle with both ends on the circle is called diameter, and it is represented by the letter D. After learning this lesson, I want to do an experiment to measure the diameter of the bowl mouth and calculate the circumference of the bowl mouth.

When I got home, I took a bowl and carefully measured the diameter of the bowl mouth with a ruler, but there were some difficulties, such as measuring the wrong diameter and finding the wrong center of the circle, which made me very headache. I thought hard and finally decided to turn the bowl upside down, draw a circle around the mouth of the bowl on the paper, and then find the center of the circle on the paper. Where is the center of the paper, the center of the bowl is there. Finally, I measured the diameter of the bowl-15cm. Knowing the answer, I jumped three feet. It seems that my efforts have not been in vain. Then, I remembered the formula of circumference: C=d, so I multiplied 3. 14 by 15 to get 47. 1cm, which is the circumference of the bowl. After working out the answer, my heart is full of joy, because I can apply mathematics to my life, I have strengthened my knowledge of circle and improved my practical ability. It's killing two birds with one stone.

There is mathematics everywhere in my life, and I will seriously find and solve more mathematical problems in my life.