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 Write-up

Title

Clothes Shopping

Problem Statement
Melanie is shopping for work clothes.  She has found a dress for \$75 and a two-piece suit for only \$60.  She does not have enough money for both, so she must choose only one.  Of course, both are "dry clean only."  If her dry cleaner charges \$4.50 for a dress or \$3 for each piece of a suit, which will be a better deal in the long run?  How many times will she have to dry clean the purchased item before it is the better deal?

Problem setup

Melanie is shopping and she wants to buy an outfit that will have to be dry cleaned. She finds a dress and a two-piece suit. The dress is 75.00 and the suit is 60.00. To dry clean the dress, it will cost 4.50 each time and to dry clean the suit will cost 6.00 each time. Which outfit is a better deal in the long run? How many times will she have to clean the item she purchases in order for it to actually be the better deal?

Plans to Solve/Investigate the Problem

I planned to write out my answers on a piece of notebook paper. I thought about simply adding the dry cleaning cost each time to each outfit.

Investigation/Exploration of the Problem

Here is what I discovered:

Cost of dress + dry cleaning               Cost of suit + dry cleaning

Dry cleanings:

ONCE                        79.50                                                       66.00

TWICE                       84.00                                                       72.00

THRICE                     88.50                                                        78.00

FOUR TIMES            93.00                                                        84.00

FIVE TIMES              97.50                                                       90.00

SIX TIMES                102.00                                                      96.00

SEVEN TIMES         106.5                                                        102.00

EIGHT TIMES          111.00                                                      108.00

NINE TIMES             115.50                                                      114.00

TEN TIMES               120.00                                                      120.00

ELEVEN TIMES      124.50                                                       126.00

So, after eleven dry cleanings, I found that the 75.00 dress as compared to the 60.00 suit is the better deal.

Author & Contact
Pam Joseph