You can use this simple formula:

=AVERAGE(ArrayFormula((REGEXREPLACE(TO_TEXT(A44:H44),"L",""))*1))

Functions used:

• TO_TEXT
• REGEXREPLACE
• ARRAYFORMULA

##EDIT (following OP's comment)

To exclude empty cells (which are counted as zeros altering the result) we adjust the formula by adding the FILTER function.

=AVERAGE(ArrayFormula((REGEXREPLACE(TO_TEXT(FILTER(A44:H44,A44:H44<>"")),"L",""))*1))

Initial answer

You can use this simple formula:

=AVERAGE(ArrayFormula((REGEXREPLACE(TO_TEXT(A44:H44),"L",""))*1))

Functions used:

• TO_TEXT
• REGEXREPLACE
• ARRAYFORMULA
• FILTER