The given expression is solved by using BODMAS rule which means the given expression will be solved in order of: Brackets, of, division, multiplication, addition and subtraction.
$5.49 per hamburger x 2 hamburgers=$10.98 $1.75 per soda x 4 sodas=$7 $10.98+$6.25+$12.99+$7=$37.22 $37.22 x 0.07 sales tax=approximately $2.61 $37.22 x 0.2 tip=approximately $7.44 $37.22+$2.61+$7.44=$47.27