# Calculus--Almost figured out

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Sports store is having a closing down sale, all stock has to be sold. each day an article remains unsold, the price is discounted by 4% of the previous days price. This discounting continues until the article is sold. The table shows the price of a mountain bike during the first 5 days of the sale:

Day 1 = 750
Day 2 = 720
Day 3 = 691.20
Day 4 = 663.55
Day 5 = 637.01

A) State the growth factor

720/750 = 0.96

B) Calculate the cost of the mountain bike on the 10th day of the sale.

T10 = 750(0.96)^10-1
= 750(0.96)^9
750(0.69253) = 519.40

C) Write an expression for the cost of the mountain bike on the nth day of the sale:

\$750(0.96)^n-1

D) The mountain bike was eventually sold for \$359.70. On which day of the sale was it sold?

I don't get how to solve this one.

• Calculus--Almost figured out -

For D)
look at the log portion of this post,
I believe it was your post, but I can't tell since you continue to use "anonymous" for your name.

http://www.jiskha.com/display.cgi?id=1316650359