Question

5*{16+[25-(12:a:2)*9]:8}:9=10​

Answer 1

{16+[25-(12:a:2)×9]:8}:9=10:2

{16+[25-(12:a:2)×9]:8}:9=5

16+[25-(12:a:2)×9]:8=9×5

16+[25-(12:a:2)×9]:8=45

[25-(12:a:2)×9]:8=45-16

[25-(12:a:2)×9]:8=29

25-(12:a:2)×9=8×29

25-(12:a:2)×9=232

(12:a:2)×9=232-25

(12:a:2)×9=207

12:a:2=207:9

12:a:2=23

12:a=2×23

12:a=46

a=46:12

a=3,8(3)