Answer: the awnser to this question is 15
Step-by-step explanation:
First you will divide the typing speed and the total number of words by the speed 2000 ÷ 50
Then divide bobs typing speed by 2000 equation 2000÷80 once you get the total both you will subtract the 2 totals together and get 15 as your awnser.
Hoped this helped!