I have an error in my SQL syntax when I convert the query from default floating-point to decimal point

Question

Using PHP and MariaDB my knowledge is fairly good. My knowledge in running 100% MariaDB is stack overflow and Google and online courses. I googled how to fix this issue converting to decimal point for 2 hours. Found this out use 1 of these 2 “AS DECIMAL(8,5)” or “DECIMAL(8,5)” to convert to decimal none of these work for me.

All the percentage columns in the table are all decimal(8,5). I read on Google when you run a SQL query defaults too floating-point. My problem is I do not know how to convert to decimal(8,5), I need 100% accuracy.

I have the table down below and the SQL query down below. Can you please show me how to convert it to decimal.

I have shortened table names to make it look better.

Table

1_player	2_player	3_player	id1_TA	id2_TA	id3_TA	avg_TA
2	16	30	85.00000	100.00000	100.00000	100.00000
10	9	9	100.00000	100.00000	100.00000	100.00000
11	2	15	100.00000	85.00000	100.00000	100.00000

Code

UPDATE test 
SET `avg_TA_percent` = (`id1_TA_percent` + `id2_TA_percent`+ `id3_TA_percent`) / 3
WHERE `id1_TA_player` = 2 || `id2_TA_player` = 2 || `id3_TA_player` = 2;

Thank you for your help.