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① Eight chickens and 15 rabbits have () feet ② () chicken and 6 rabbits have 36 feet ③ The chicken and the rabbit have 48 feet ④ How many rabbits and chickens are there in the cage,
1. 8x2+15x4=76
2.36-6x4=12 12/2=6
There are many answers, such as 6 chickens and 9 rabbits, 8 chickens and 8 rabbits, etc
4.6 heads means that there are 6 chickens and 6 rabbits
The first one is 6x4 = 24 24-20 = 4 4 / 2 = 26-2 = 4, so there are 4 rabbits and 2 chickens
The second is 6x2 = 12 20-12 = 8 8 / 2 = 4 6-4 = 2, so 4 rabbits and 2 chickens
1. Mix 10 socks of blue, white and black together, and take at least a few socks at a time to ensure that there must be one pair of socks of the same color. What if you want two pairs of socks of the same color?
2. There are 20 balls in blue, white and black,
(1) At least a few balls can guarantee two pairs of balls of the same color
(2) At least a few balls can guarantee three teams of the same color
3. There are 10 red, yellow and blue balls of the same size in the box. If you want to find three balls of the same color, how many balls should you touch at least?
Of course, it's better to put it in one category,
Can you write it more clearly? How can you write the formula
1:4,6
2:(1)6
(2)8
3:7
The same method: such as 3: the most difficult to touch 6 red, yellow and blue have two, and then set 3 of the same color
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