Examination questions of seventh grade mathematics Olympic competition.
1. There is a string of numbers 1996 2808864 ... The arrangement rule of this string of numbers is: starting from the seventh number, each number is a single digit of the sum of the first two numbers. Then the 65438th bit+0999th bit of this series is (), and the sum of the 65438th bit+0999th bit is (). 2. There is a cell that divides once every minute, and one cell can be divided into nine at a time. 1999 minutes later, these cells were put into 7 test tubes on average, leaving () cells. 3. Use the symbol (a) to represent the integer part of A, such as (10,62) =10, (15÷4)=3, then (120 ÷ 7) × (9 5. The printing factory needs to print 270,000 copies of mathematical oral calculation books, 2855 copies a day in the day shift, and 290 copies more in the night shift than in the day shift. When completing the task, the number of copies printed in the day shift is less than that in the night shift. 6. On both sides of a 2000-meter-long highway, plant one poplar every 10 meter, and plant three maples every two poplars at the same distance. There are * * * kinds of maple trees on both sides of this highway. 7.8. Xiaoming rode on the back of an ox and drove four buffaloes across the river. These four cows need two minutes, three minutes, six minutes and eight minutes to cross the river respectively, and only two cows can be driven across the river at a time. Then it will take Xiao Ming at least () minutes to get all the cows across the river. 9. The Customs Building has twelve floors. Ping Li's father works on the tenth floor. One day, Ping Li went to see her father. It took her 40 seconds to walk from the first floor to the fifth floor. At this speed, it will take her at least () seconds to get to her father's office. 10. Xiaoling 12 years old, and her mother is 40 years old this year. When the mother's age is five times that of her daughter, the sum of the ages of mother and daughter is () years old. 1 1. Xiao Wei left home to visit Zhaobaoshan, 26 kilometers away. His riding speed is 18 km per hour, and the running speed of hounds is twice as fast as riding speed. When the hounds run to the foot of Zhaobaoshan, if Xiao Wei hasn't arrived yet, they will immediately return and run to meet Xiao Wei, and then run to Zhaobaoshan after meeting Xiao Wei ... so they run back and forth until Xiao Wei arrives at Zhaobaoshan. At this time, the hound ran () kilometers. 12. There are a set of formulas: 1+ 1, 2+3, 3+5, 1+7, 2+9, 3+1,/kloc-0. 13. There are two trains. This bus is 200 meters long and travels 30 meters per second. This truck is 300 meters long and travels 20 meters per second. Two cars run side by side on parallel tracks in the same direction, and after () seconds, the passenger car overtakes the truck; If two cars drive in opposite directions, it takes () seconds from meeting to passing by. 14. There are 15 questions in the fourth grade math contest paper. Answer one question correctly and get 10; If you do a wrong question, deduct 4 points; No answer, 0 points. Li Chen got 88 points, but she didn't answer the question (). 15.4 (2) Class held the "June 1st" Gala, and the counselor and teacher took a sum of money to buy candy. If they buy mango 13kg, the difference is less than 4 yuan. If they bought toffee 15kg, there would be 2 yuan left. It is known that mango is 2 yuan a catty more expensive than toffee, so the counselor and teacher brought () yuan. Reference answer 1. (2) (8003) 2.(2) 3.( 1 19) 4.(90) 5.( 13050) 6.( 1200) 7.2) 12.(998) (3998) 13.(20) ( 10) 1 4. (2)15. (152)1. A: Wednesday and Saturday. 2. There are five Saturdays and four Sundays in 10 of a certain year. What day is October 1st this year? Answer: Monday 3. The first column, the second column, the third column, the fourth column and the fifth column 6171016161949/kloc-0. (2) Where is the row of1000? A: The fourth and third columns. Use 5÷ 14. What is the number1997th after the decimal point of the quotient? Answer: What is the sum of 200 1 digits after the decimal point of the quotient? Answer: 2001÷ 6 = 333 ... 3, (1+4+2+8+5+7) × 333+1+4+2 = 8998 6.65438 series+0,3. Answer: 0 7. Arrange the natural numbers of 1- 100 in the following order: Answer: The sum of 9 numbers in a square is 90. Can you frame 9 numbers like this so that their sums are 170, 2 16 and 630 respectively? Analysis and solution: first observe the characteristics of 9 numbers. The average of the upper and lower numbers is 10, and the average of the left and right numbers.