hey /sci/,

First time business math class taker
>inb4 no homework help questions
>inb4 /wsr/ is that way
I know this isn't a "post your homework help" here, but I'm not asking for "homework help"
I'm simply asking if someone can point out where I'm wrong, or if it's a mistake by the teacher.

I'll post a pic related, with all shown work.