Interesting math problems in the first semester of junior high school
1. A mouse stole the corn. Of the total110 and10, it ate the remaining 1/9 and 1/9 on the second and third days. Four people, Xiao Zhao, Tia Xiao, Sun Xiao and Xiao Li, discussed which team won the final of the football match. Xiao Zhao said, "Team D will lose, but Team C can win." Penny said, "Team A and Team C are better than Team B, and there will be losses at the same time." Sun Xiao said: "Team A, Team B and Team C can all win." Xiao Li said, "Team A lost, while Team C and Team D obviously won." They have said which team won. Can you guess which team won the championship? 3. It is reported that the domestic water price of Wuhan residents will be adjusted for the fourth time since 1999. Residents' monthly water consumption is 22 cubic meters or less, which is the first-class water consumption base and charged according to the adjusted domestic water price. More than 22 cubic meters, less than 30 cubic meters (including 30 cubic meters) of the part for the secondary water base. 0.5 times the adjusted price of 65438+. The part exceeding 30 cubic meters is the third-level water consumption base, which is charged at twice the adjusted price. It should be known that the adjusted domestic water consumption price of residents will rise from 1.5 1 yuan per cubic meter to 1.96 yuan. According to the average monthly household water consumption, Mr. Zhang calculated as follows. According to the current new price, he has to pay 74.5 yuan a month. How much more water does his family pay each month on average than before the adjustment? Xiaoming is in the street, and a bus 1 comes head-on every 6 minutes. Every 12 minutes, a bus of 1 passes him from behind. If every car has the same speed and the same departure interval, then a car will come every few minutes from the starting point. Xiao Ming and Xiao Li were born in 1998. But both of them are Fridays and Xiao Ming was born earlier than Xiao Li. The sum of their birth dates is 22, so Xiao Li's birth date is: a:15 b:16 c; 17 No. D: 18 No 6. 1999 times 200 1 divided by 30000000000000?