Shifting advertising money

Prompt:

A firm recently spent $100 on Google AdWords and generated 100 extra visits to the firm’s website, 5 of which resulted in a purchase. To pay for the change, they dropped the banner advertising on ESPN.com saving $1000, which also reduced the number of visits to their website by 500 and 20 fewer sales. Sales from visitors from ESPN.com were on average 25% higher than sales from visitors from Google AdWords.
Evaluate and discus the decision to shift advertising money from ESPN.com to Google AdWords.