Help needed with expressions with substring expressions.

Just like algebra, you start with the innermost parentheses:
here's a hint without the answer:
1. Do the RIGHT() fⁿ
2. Use the LEFT on the results of the RIGHT....

Remember that in the nested functions, the functions are evaluated from inside out.
So in this formula you are using two functions Left and Right, where Right is used inside the Left function so it will be evaluated first.
In the Left function there are two arguments you need to pass within it i.e. Left(Text,No. of left most Characters you want to extract from the Text), so instead of passing the Text or a cell reference as a first argument in the Left function, you are passing another function Right as an argument in place of Text, so whatever your Right function returns would be used as the first argument for the left function.
If you look at your Right function =RIGHT("transparent",7), it will return 7 characters from the right of the string transparent i.e. sparent.
So you Left function would become like this Left("sparent",5) and that will return the 5 characters from the left of the string sparent i.e. spare

You're welcome.

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