Mathematical problem
In June, the output increased 10%, and in July, the output decreased 10%. Is the output in July more or less than that in May?
The output of a factory increased 10% in June and decreased 10% in July. Is the output in July more or less than that in May?
Answer: July is less than May. If the output in May is 10, the output in June is 1 1, and the output in July is11-/kloc-0% ×1= So July is less than May.
Math puzzle: How many games does it take to produce a champion?
128 how many times does it take a pair of players to participate in the tennis mixed doubles competition to win the championship?
A mixed doubles tennis tournament was held in a small town. A * * * There are 128 couples who signed up for this competition. The tournament manager stayed up for half a night before drawing up the schedule. So, do you know how many mixed doubles competitions will be held before the champion is born?
Interpretation of tennis mixed doubles: each team sends a man and a woman to play together.
A: Because one pair of players will be eliminated in each game, there will be 128 pairs of players because of a * * *, so there will be 127 elimination matches before the champion team is produced.
Math puzzle: Count how many buildings are on both sides of the street.
Count how many buildings are on both sides of the street.
The buildings on the street are numbered from 1 to the end of the street, and then from the building on the opposite street to the building numbered 1. Each building is just across from the opposite building.
If the building with the house number 12 1 is opposite the building with the house number 294, how many buildings are there on both sides of this street?
A: There is 12 1 between the building and the beginning of the number. Accordingly, there are 120 buildings with numbers higher than 294. So there are 294+ 120=4 14 buildings on both sides of the street.
Math puzzle: Calculate how many people can get out of danger safely when a passenger ship hits the rocks.
Calculate how many people can escape safely from the collision between the passenger ship and the rock.
A long time ago, a foreign passenger ship ran aground and there was only one rescue ship. This ship can only hold five people. The nearest island is also four minutes away. In 20 minutes, the passenger ship will sink with 25 people on board. How many people can escape safely?
Answer: If it takes 4 minutes to reach the island, it takes 8 minutes to go back and forth. Let five people go to the island by boat first, because one person had to row the boat back, so only four people took refuge on the island (it took eight minutes and four people were rescued). Then 5 people were taken to the island, 1 people came back by boat (16 minutes, 8 people were rescued). There were five more people on board and they left, so there was no time to come back to pick them up. When the ship reached the island, it had sunk. So at most 13 people can escape safely.
Math puzzle: Calculate how many days it takes a frog to climb out of the 18m deep well.
Calculate how many days it takes a frog to climb out of the 18m deep well.
A frog fell into a well 18 meters deep. Climb 6 meters every day and drop 3 meters at night. At this rate, how many days can it climb out of the wellhead?
Answer: Many careless people have calculated that the answer is 6 days. Their idea is that frogs climb 6 meters every day and 3 meters every night, so they climb 3 meters every day on average, and the well depth is 18 meters, so frogs climb out of the wellhead after 6 days. They ignored the most crucial point, that is, the frog stopped falling when it climbed out of the wellhead on the last day. So the correct answer is that frogs can climb out of the wellhead in only five days. The frog * * * climbed 12 meters four days ago, and on the fifth day, the frog climbed out of the wellhead just after climbing the remaining 6 meters.
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