Find the number of even positive number which have five digits.

Explanation

To find the number of even positive five-digit numbers, we can follow these steps:

### Step 1: Determine the first digit
The first digit of a five-digit number cannot be 0 (as it would not be a five-digit number). Therefore, the first digit can be any digit from 1 to 9. This gives us 9 possible choices for the first digit.

**Hint for Step 1:** Remember that the first digit cannot be zero in a five-digit number.

### Step 2: Determine the second digit
The second digit can be any digit from 0 to 9. This gives us 10 possible choices for the second digit.

**Hint for Step 2:** The second digit can include zero, unlike the first digit.

### Step 3: Determine the third digit
Similar to the second digit, the third digit can also be any digit from 0 to 9, giving us another 10 possible choices.

**Hint for Step 3:** The third digit has the same options as the second digit.

### Step 4: Determine the fourth digit
The fourth digit can also be any digit from 0 to 9, providing us with another 10 possible choices.

**Hint for Step 4:** The fourth digit follows the same rule as the second and third digits.

### Step 5: Determine the fifth digit
The fifth digit must be even to ensure the entire number is even. The possible even digits are 0, 2, 4, 6, and 8. This gives us 5 possible choices for the fifth digit.

**Hint for Step 5:** Remember that the last digit must be even, so only certain digits are allowed.

### Step 6: Calculate the total number of combinations
Now, we can calculate the total number of even five-digit numbers by multiplying the number of choices for each digit:

\[ \text{Total combinations} = (\text{Choices for 1st digit}) \times (\text{Choices for 2nd digit}) \times (\text{Choices for 3rd digit}) \times (\text{Choices for 4th digit}) \times (\text{Choices for 5th digit}) \]

Substituting the values we found:

\[ \text{Total combinations} = 9 \times 10 \times 10 \times 10 \times 5 \]

Calculating this step-by-step:

1. \(9 \times 5 = 45\)
2. Then multiply by \(10 \times 10 \times 10 = 1000\)
3. Finally, \(45 \times 1000 = 45000\)

Thus, the total number of even positive five-digit numbers is **45000**.

**Final Answer:** 45000