How to replace a combination of numbers and letters in google spreadsheets using a formula?

Question

Google Sheets

Good afternoon.
Given:
There is such a combination in the google spreadsheets table: 44.34 rubles.
Required:
To look like this: 44,34
Read https://support.google.com/docs/answer/3098245
But didn't understand what it means:
This function is not suitable for working with numbers, because its input and output have text format. If the output must be a number, use this function in conjunction with VALUE. Input data in the form of numbers must first be converted using the TEXT function.
Thanks in advance for your reply!

Answer 1

With the help of SUBSTITUTE, you first get rid of "_ruble", then from the dot. Then with VALUE you turn the text into a number.
The regular expression to apply is to shoot sparrows from a cannon.