Answer:
Mr. Chang got the better deal.
Step-by-step explanation:
Robertson: He paid 100% - 20% = 80% of the cost of the book.
80% * 29.99 = 80/100 * 29.99 = 2399.2/100 = 23.992
Chang: He paid 10% off $25.00
10% of $25.00 = 2.50 dollars. I'll let you go through the steps to get this.
With the discount, Mr. Chang paid 25.00 - 2.50 = 22.50
Conclusion
Mr. Chang got the better deal by $1.49
