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Xiao Ming and Xiao Gang collect digital cards. Xiao Ming's cards account for 16 / 11 of the total. If he gives 15 cards to Xiao Gang, they will have the same number. How many cards do they have in total?
15 × 2 = 30 sheets
The total number is: 30 ÷ [11 / 16 - (1-11 / 16)] = 80 sheets
Xiao Ming and Xiao Gang are quarreling. The teacher comes to them. At this time, they are very nervous
(fill in the allegorical sayings in brackets)
Fifteen buckets to draw water - seven up and eight down
What unit of measurement do Americans use to measure height and weight?
How much weight does "145 lbs" refer to? How to convert it to kilogram?
How high does "5'9" refer to? How to convert it to cm?
LBS is the pound force, 1lbs = 0.453kg, 145lbs = 65.7kg
5'9 "means 5 feet 9 inches, 1 foot = 12 inches, 1 inch = 2.54 cm
So 5'9 "= 69" = 175 cm
Reading questions of sixth grade father and son exercise book
"The red sun is rising in the distance" implies ();
This is a human tragedy. Why does it happen?
"The red sun is rising in the distance" implies that the victory of a just war is in sight;
This is a tragedy between people. Why did it happen? A: because the German invasion launched this unjust war
20 and 30, 14 and 21, 20 and 30, 15 and 60
60,42,60,60
The solution of 3-6-x-5-x-4 = 2x + 2-2 and the value of x-6-x = 1-2,
It's (3-x) / 6 - (x-4) / 5 = (2x + 2) / 3 + 2
The counterexample to prove that the proposition "if x (x + 2) = 0, then x = - 2" is a false proposition is?
x(x+2)=0
It also holds when x = 0
But obviously not x = - 2
It is known that the sequence {an} is an arithmetic sequence with non-zero tolerance, A1 = 1. If a1a2a5 is an arithmetic sequence, the general term formula can be obtained
Solution A1 = 1 A2 = 1 + D A5 = 1 + 4D
A1a2a5 is equal proportion, so (1 + D) ^ 2 = 1 * (1 + 4D)
D ^ 2-2d = 0 d = 2 D = 0 (rounding)
So an = a1 + (n-1) d
=1+(n-1)*2
=2n-1
Given that the maximum value of F (x) = - x ^ 2 + MX + 1 in the interval [- 2, - 1] is the maximum value of function f (x), then the value range of M is
f(x)=-x²+mx+1
Maximum = maximum
So the axis of symmetry is in the interval [- 2, - 1]
So the axis of symmetry: x = m / 2 - 2
First simplify, then evaluate
a^2+ab-ac/a^2-ab·(a-b)^2-c^2/a^2+2ab+b^2÷a^2-(b-c)^2/b^2-a^2.
Where a = 1, B = - 2, C = - 3
（a²＋ab－ac）/（a²－ab）·[（a－b）²－c²]/（a²＋2ab＋b²）÷[a²－（b－c）²]/（b²－a²）＝a（a＋b－c）/[a（a－b）]·（a－b－c）（a－b＋c）/（a＋b）²...
RELATED INFORMATIONS
- 1. A school logistics staff to a stationery shop to buy test stationery bags for ninth grade students, stationery shop rules a purchase of more than 400, can enjoy a 20% discount. If you buy a ninth grade students, can not enjoy a 20% discount, need to pay 1936 yuan; if you buy 88, can enjoy a 20% discount, also only need to pay 1936 yuan. How many ninth grade students in the school ？
- 2. Xiaoying and several students went to the stationery store to buy exercise books. The stationery store stipulated that if the purchase reached a certain quantity, they could buy them at the wholesale price. So they gathered together 60 yuan to buy them at the wholesale price. In this way, the number of exercise books purchased was 30 more than that purchased at the retail price. If the wholesale price of each exercise book was 45 times of the retail price, what was the retail price of each exercise book How much is it?
- 3. A supermarket used 80000 yuan to purchase a batch of "T-shirts" from other places. Due to the good sales, the supermarket urgently allocated 176000 yuan to purchase "T-shirts" which are twice as much as the last time. However, the second purchase price is 4 yuan more than the first purchase price. The supermarket sells them at 58 yuan per piece, and the remaining 150 pieces are sold out at a 20% discount. How much money has the supermarket made in this business (including two purchases)?
- 4. Every day, the supermarket bought back a batch of T-shirts from other places with 50000 yuan. Due to the good sales, the mall urgently allocated 186000 yuan to buy back T-shirts that were twice as much as the first time. However, the second time was 12 yuan more expensive than the first time. The mall sold them at the price of 80 yuan. In order to shorten the inventory time, the last 400 T-shirts were sold out at a discount of 6.5% How much is the profit of the Communist Party of China?
- 5. In order to promote a product priced at M yuan, supermarket a, supermarket B and supermarket C cut prices by 20% twice in a row, 40% at a time in supermarket B, 30% at the first time in supermarket C and 10% at the second time. At this time, the most cost-effective supermarket for customers to buy this product is () A. A B. B C. C D. B or C
- 6. In order to promote a commodity with the same price, supermarket a, supermarket B and supermarket C cut prices by 20% twice in a row, 40% at a time in supermarket B, 30% at the first time in supermarket C and 10% at the second time. Which supermarket is more cost-effective for customers to buy this commodity A. B. B. C. C. D
- 7. I bought a pen, notebook, stationery and schoolbag in the mall
- 8. The stationery store bought 100 pens at the price of 4 yuan each, and each pen was sold at 6 yuan. When some pens were sold, the remaining pens were sold at a 10% discount. When all pens were sold, the store made a total profit of 188 yuan. How many pens were sold at a 10% discount? Don't use the equation, but use the formula
- 9. Buy 3 pens in a stationery shop and get 2 free pens, 4 yuan each. How much should I pay for 12 pens?
- 10. The school plans to buy 40 pens and some notebooks (the number of notebooks exceeds the number of pens). The price of both a and B plus the stationery shop is 10 yuan for each pen and the number of notebooks It's 2 yuan per book. The preferential way of shop a is 10% off for pens and 20% off for notebooks. Shop B's preferential way is to give one notebook for every five pens. Pens are not discounted, and notebooks are 7.5% off. So how to buy more cost-effective (please see the title and come back) good bonus points
- 11. At the school sports meeting, in the 200m sprint, Xiaoqiang took 2 / 3 minutes, Xiaogang took 50 seconds and Xiaoming took 0.6 minutes. Which of them is the fastest?
- 12. It took Xiaoming 18 seconds to run 100 meters and Xiaogang 24 seconds to run 150 meters. Who runs fast? process
- 13. Xiao Gang and Xiao Ming are in the 100 meter race. When Xiao Gang runs 80 meters, Xiao Ming is 40 meters away from the end. Then when Xiao Gang runs to the end, how many meters is Xiao Ming away from the end?
- 14. The mathematics interest group held a test. There were 15 questions in the whole paper. It was stipulated that 8 points would be deducted for each right question and 4 points would be deducted for each wrong question. Xiaoying got 72 points in total, and she did it right______ Question
- 15. The mathematics interest group held a test. There were 15 questions in the whole paper. It was stipulated that 8 points would be deducted for each right question and 4 points would be deducted for each wrong question. Xiaoying got 72 points in total, and she did it right______ Question
- 16. Xiao Ming went to school from home. After walking at the speed of 50 meters per minute for two minutes, he found that he would be 8 minutes late if he walked at this speed Xiao Ming went to school from home. He walked at a speed of 50 meters per minute for two minutes. He found that he would be 8 minutes late if he walked at this speed. So he accelerated his pace and walked 10 meters more per minute. As a result, when he got to school, he had five minutes to go. What's the distance between Xiao Ming's home and school?
- 17. When Xiao Ming reads a book, the number of pages he has read is 32 of the number of unread pages. When he reads another 30 pages, the number of pages he has read is 73 of the number of unread pages. How many pages are there in this book?
- 18. Help me solve a math problem and answer it in a minute! When Li Mengmeng read a book, he read one third of the whole book on the first day, and 18 pages more than 25% of the whole book on the second day. At this time, the ratio of the number of pages read to the number of pages not read is 3:1. (1) how many pages are there in the book? (we can't use equations to solve it, we must use equations) (2) how many pages did he read the next day?
- 19. The circumference of a cuboid is 80cm, and the ratio of length to width is 4:1. What's the area of the cuboid? Tao Jie and Jiang Tao travel from a to B at the same time, and their speed ratio is 4:3. Tao Jie travels 20 kilometers per hour, and Jiang Tao travels how many kilometers per hour?
- 20. Master Wang made a light box with 78.5 square centimeters of openings in the middle of the top and bottom. How much colored paper did he use? 20cm in diameter