PROGRAMMING:1 / (1 * 2) + 1 / (2 * 3) +... Error
Find the approximate value of the following expression, the error is less than 0.0001.
###Output format:
Directly output the real result with 6 decimal places, without any additional characters.
###Output example:
```out
zero point nine nine zero zero zero zero
```
answer：If there is no answer, please comment
###Output format:
Directly output the real result with 6 decimal places, without any additional characters.
###Output example:
```out
zero point nine nine zero zero zero zero
```
answer：If there is no answer, please comment