Answer: 60 words per minute
Work Shown:
40 words = (2/3) of a minute
3*40 words = 3*(2/3) of a minute ... multiply both sides by 3
120 words = 2 minutes
120/2 words = 2/2 minutes .... divide both sides by 2
60 words = 1 minute
Bob's speed is 60 words per minute (wpm)