Leo dug up 6 4/5 pounds of treasure on his first dig. Anne dug
up 4 1/2 pounds of treasure. How
much more treasure did Leo dig
up than Anne?

you can solve this problem using a long method to further understand the relationship of each decline in sales.

400,000 cd x 17% = 68,000

one year from now, the sales would be 332,000 (400,000 – 68,000)

332,000 cd x 17% = 56,440

two years from now, the sales would be 275,560 (332,000 – 56,440)

275,560 cd x 17% = 46,845

three years from now, the sales would be 228,755 (275,560 – 46,845)