How many ways to put four different balls into three different boxes?

How many ways to put four different balls into three different boxes?

Each ball has three ways to put, a total of 3 * 3 * 3 * 3 = 81 kinds

There are several ways to put three balls in three boxes
Why not C (3,1)

It's a complete permutation of 3. 3 × 2 × 1 = 3!

There are 158 cards in red, white and black. They are arranged in the order of five red cards, three white cards and four black cards. What color is the last card
Don't die

158 divided by (5 + 3 + 4) = 13.2, the second is red

Put 10 balls of red, yellow and white into a bag. Take at least () balls to ensure that you can get 3 balls of the same color?

21
To do the worst idea, we have 20 requests, 10 red, 10 yellow, and another one, which must be white

Put 10 balls of red, blue, green and black into a bag, and take at least () balls to ensure that two balls of the same color can be taken
A. 3B. 4C. 5D. 8

The worst case is: touch out four balls, red, blue, green, black four colors each one, so as long as you take one more ball, you can guarantee to get two balls of the same color, that is 4 + 1 = 5

There are five balls in red, yellow and white, which are put in one bag. At least () balls can be taken to ensure three balls of the same color,

7

Congcong: there are red, white, blue and black monochromatic balls in the bag. Take several balls out of the bag at will. Mingming asked: how many balls must be taken out to ensure that there are three balls of the same color?

2 × 4 + 1 = 9, a: at least 9 balls must be taken out to ensure that there are three balls of the same color

There are three kinds of red, yellow and blue balls in the pocket. In order to take out three small balls of the same color, at least how many balls need to be taken out of the pocket?
Urgent

2*3+1=7

There are 10 balls in each of the three colors in the bag. How many balls can be found at least once to ensure that the five balls are of the same color?

Touch 5 at a time and the same color is possible, but the probability is too small
If you have to guarantee 5 of the same color, at least 13 (4 of each color, any one more can guarantee)

Six red, yellow and blue balls are put in a bag. After mixing, you know how many balls you can find to ensure that two of them are of the same color

3 colors
When you touch three balls, if you don't have two of the same color
If you touch another one, there must be two of the same color
So it's four