Xiaodong has a bicycle with a diameter of about 66cm. If the average speed is 100 cycles per minute, the distance from home to school is 2000m. How many minutes does it take?

66 cm = 0.66 m, wheel circumference: 3.14 × 0.66 = 2.0724 (m), speed per minute: 2.0724 × 100 = 207.24 (m), time required: 2000 △ 207.24 ≈ 10 (min), a: about 10 minutes

RELATED INFORMATIONS

1. The side length of a square lawn is increased by 2 meters, and the area is increased by 40
2. 1. On an east-west freeway, there are two cars a and B driving westward. The speed of car a is faster than that of car B, and there is a certain interval between them___ As a reference, car a moves westward and car B moves eastward_____ As a reference, both AB and ab move eastward 2. An object moves in a straight line for 6 seconds. The average velocity in the first 2 seconds is 6 m / s, and the average velocity in the last 4 seconds is 3 M / s 3. The distance between Party A and Party B is 162km. The car starts from place a at the speed of 10m / s. after driving 72km, it drives to place B at the speed of 45km / h. The average speed of the car from place a to place B is calculated 2.3 write the process: known; seek; solve; answer
3. The distance between the two feet of the compass is set at 3cm. What are the circumference and area of the circle drawn?
4. Find the minimum positive period of function f (x) = 2 (sin2x) ^ 2 + 4sin2x * cos2x + 3 (cos2x) ^ 2, and find the minimum and maximum
5. Divide a circle into 16 equal parts to form a short-sighted rectangle. The circumference of the rectangle is 41.4, and its area is
6. If a set of data x1, X2, x3.xn is known, the average is a, the variance is B, and the standard deviation is C If we know that the average of a set of data X &;, X &;, X &;. Xn is a, the variance is B, and the standard deviation is C, then the average of another set of data 3x &; - 2,3x &; - 2,3x &; - 2,. 3xn-2 is variance, and the standard deviation is C
7. If the perimeter of a large square is 20cm longer than that of a small square, the difference in area is 35cm2 What is the length of each side of the two squares?
8. Parameter estimation problem: let the population obey the uniform distribution of θ - 1 / 2 to θ + 1 / 2, x1, X2 Xn is the sample from the population, and the sample mean is x average Let the population obey the uniform distribution from θ - 1 / 2 to θ + 1 / 2, x1, X2 Xn is the sample from the population. The mean value of sample X and (x (1) + X (n)) / 2 are unbiased estimates of θ. Which is more effective? The key is how to find the variance of (x (1) + X (n)) / 2. X (1) represents the minimum value of n samples, and X (n) represents the maximum value of n samples
9. Each classroom is 8.25 meters long and 4.5 meters wide. The floor is paved with square bricks with an area of 0.25 square meters. How many bricks does it take to pave a classroom
10. Find ∫ ln [e ^ (x) + 1] / e ^ (x) DX
11. Given that the area of a circle is 78.5cm, the circumference of the circle is
12. （2X-Y）²-4（X-Y）*（X+Y）-（X-Y）*（X-1）
13. In the parallelogram ABCD, E.F AB.AD And BF = De, BF and de intersect at point P, the bisector angle c of CP is proved
14. It is known that, as shown in the figure, a is a point on EF, and the quadrilateral ABCD is a parallelogram with ∠ ead = ∠ BAF. (1) prove that △ CEF is an isosceles triangle. (2) which two sides of △ CEF are equal to the perimeter of the parallelogram ABCD? Prove your conclusion
15. As shown in the figure, divide the diagonal AC of the square ABCD into 6 segments, and make a square with each segment as the diagonal. Let the sum of the circumference of the six small squares be p, square ABCD What is the relationship between P and l?
16. The starting price of a taxi in a city is 5 yuan (within 3 km), and the average price is 1.5 meters per kilometer for more than 3 km. Xiaomin's family pays 8.9 yuan for the distance between them when they go to grandma
17. As shown in the figure, if there is a point E in the square ABCD and the triangle EBC is an equilateral triangle, what is the degree of ∠ bea?
18. Given the position of a, B and C on the number axis as shown in the figure, try to simplify: | A-B | + | B-C | + | c-a| As shown in the figure: ———|————————|————|————————|—→ c 0 a b
19. If the positions of numbers a and B on the number axis are shown in the figure, then | B | - | a | = -? - a -------- - 0 -------- B is simplified
20. 15. The position of a, B and C on the number axis is shown in the figure, which is simplified |a|+|b|+|c|-|a+b|+|b-1|-|c-a| ____ C_______ b_____ 0__ 1_____ a