With the 10 numbers from 0 to 9, you can make up the even number of three digits without repetition 1. When the mantissa is 2, 4, 6 and 8, the number of bits combined is 4. Because the hundreds cannot be 0, the number of bits combined is 8, and the number of bits combined is 8 × 8 × 4 = 256 2. When the mantissa is 0, the combination of 100 bits is 9, the combination of 10 bits is 8, and the total number of combinations is 9 × 8 × 1 = 72 Total 256 + 72 = 328 On the basis of this classification, I have a question: why should we take the hundred first, if we take the ten first. Process 1: there are 9 combinations of ten (ten can take 0), and 7 combinations of hundred

With the 10 numbers from 0 to 9, you can make up the even number of three digits without repetition 1. When the mantissa is 2, 4, 6 and 8, the number of bits combined is 4. Because the hundreds cannot be 0, the number of bits combined is 8, and the number of bits combined is 8 × 8 × 4 = 256 2. When the mantissa is 0, the combination of 100 bits is 9, the combination of 10 bits is 8, and the total number of combinations is 9 × 8 × 1 = 72 Total 256 + 72 = 328 On the basis of this classification, I have a question: why should we take the hundred first, if we take the ten first. Process 1: there are 9 combinations of ten (ten can take 0), and 7 combinations of hundred

Because the hundred is very special, three digits, the hundred cannot be equal to 0, and the three digits are even, so we need to determine the number of digits first
If the single digit is 0, there is no requirement for the 100 and 10 digits
If the digit is not zero, then if you want to remove 0 from the 100 digits, only 8 digits can be selected, while 10 digits are not required

With the 10 numbers from 0 to 9, the number of even three digit numbers without repetition is ()
A. 324B. 328C. 360D. 648

When the mantissa is 2, 4, 6 and 8, there are four ways to choose the individual position. Because the hundred position cannot be 0, there are eight ways to choose the hundred position, eight ways to choose the ten position, and a total of 8 × 8 × 4 = 256. When the mantissa is 0, there are nine ways to choose the hundred position, eight ways to choose the ten position, and a total of 9 × 8 × 1 = 72

A = 1 / 2 times b = 1 / 3 times C, where a, B and C are three three digit numbers. They use nine numbers from 1 to 9 to make the equation hold, ABC respectively
How much is it

There are four sets of data to meet the following requirements:
1.192,384,576
2.219,438,657
3.273,546,819
4.327,654,981