Math diary fan Wen Yi:
Today, I had a meaningful math class. The teacher asked us to play a game called racket ball. The teacher divided the class into two teams, team A and team B. Five seconds later, I was assigned to the first team. I thought, "I have played before, and it will definitely add luster to our team." I raised my hand confidently. I was chosen, and I am very happy.
I don't care whether I am the third or the first, as long as I choose which one. I am both excited and nervous, and the game has started. The small audience in the seat shouted for their team: "Come on! Come on! " After filming No.1, there was a burst of applause at the scene, and the classroom became a sea of joy. The second and third contestants also took pictures, and the rear wheel came to me. I was so nervous that I only took five shots, and the result was that team B won!
Math diary fan Wen Er:
Today, we learned the circle in math class. The first is the method of drawing a circle. Can be compared with the cup bottom or cup cover, and turn around it; You can use shoelaces, one end is tied with a pen, and the other end is fixed in one place. Straighten the shoelaces, keep the fixed end still, and turn the end with the pen once. The length of the shoelace determines the size of the circle. The long ones are big and the short ones are small. You can also use your arms, take your shoulders as the center, hold a pen and draw a circle.
The easiest way is to separate your feet with compasses first. The length of the separation depends on the radius of the circle to be drawn. The pointed foot is fixed on the paper, and the other end rotates around the pointed foot. When painting, the pointed feet can't move, and if they move, they can't draw a complete circle. When the leg plans a circle, the point where the toe is located is called the center of the circle, which is generally represented by the capital letter o; The line segment connecting the center of the circle and any point on the circle is called the radius, which is generally expressed by the lowercase letter "R", and the length of the radius is also the distance between two feet of the compass.
Math diary Fan Wensan:
One day, Xiaoming is going to pay the electricity bill. Suddenly, he found that in order to encourage electricity conservation, the power company revised the previous charging method, and it became: each key electricity consumption does not exceed 100 kWh, and it is charged at 0.52 yuan per kWh, while each open electricity exceeds 100 kWh, and the excess is charged at 0.6 yuan per kWh. This can blind Xiao Ming, you know, he knows nothing about mathematics! No way, she had to go home. Xiaomingjia 10 * *121kwh, how to calculate? At this time, Xiao Ming's sister came back.
Seeing her brother's sad face, she asked him what had happened. Finally figured it out, Xiaohong decided to help the math idiot. She sat down and patiently explained to Xiao Ming: Our monthly electricity consumption exceeds 100 kWh,121-100 = 21(kWh), 21x0.6 =/kloc-.