#10 - Do 31 - 8 and you will get 23. #12 - Do $12.35 - $8.95 and you will get $3.40 #14 - Do $95 - $73 and you will get $18 #16 - Do $225 + $548 and you will get $773 #18 - It is 3 since Paula had to suntract 7 from both sides and that ended with x = 3