The expression is 40w.
= 40(0.5) (Substitute w = 0.5)
= 20 (Multiply: )
The value of the expression is 20.
![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/step1.JPG\")
![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=723ce87be0c76ec680d7ca18c061c0d1.png\")
)![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/solution.JPG\")