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 Write-Up

Title

Planning a Cruise

Problem Statement
A cruise line has 3-day, 4-day and 7-day cruises. After each cruise, a ship returns for one day and repeats the pattern. If one cruise of each type leaves today, when will all 3 cruises leave again on the same day?

Problem setup

I used Microsoft Word to help me with this. I put 3 bold-faced headings on the page. They were 3-day cruise, 4-day cruise and 7-day cruise.

Plans to Solve/Investigate the Problem

I planned to solve this problem by typing in the dates for each ship starting with today's date which is October 18, 2005. I then planned to add the number of days for each cruise length and one day on the return. Then, I would eventually be able to "hit" upon the date that all 3 ships left again on the same day.

Investigation/Exploration of the Problem

The following is the Word document with the dates listed. According to my chart, all 3 ships will leave again on November 27, 2005:

3 day cruise ship:

October 18-3 day leaves

October 21- 3 day returns

October 22- 3 day leaves again

October 25- 3 day returns

October 26- 3 day leaves again

October 29- 3 returns

October 30- 3 leaves again

November 2- 3 returns

November 3- 3 leaves again

November 6- 3 returns

November 7- 3 leaves again

November 10- 3 returns

November 11- 3 leaves again

November 14- 3 returns

November 15- 3 leaves again

November 18- 3 returns

November 19- 3 leaves again

November 22- 3 returns

November 23- 3 leaves again

November 26- 3 returns

November 27- 3 leaves again

4 day cruise ship:

October 18- 4 day leaves

October 22- 4 day returns

October 23- 4 day leaves again

October 27- 4 day returns

October 28- 4 day leaves again

November 1- 4 returns

November 2- 4 leaves again

November 6- 4 returns

November 7- 4 leaves again

November 11- 4 returns

November 12- 4 leaves again

November 16- 4 returns

November 17- 4 leaves again

November 21- 4 returns

November 22- 4 leaves again

November 26- 4 returns

November 27- 4 leaves again

7 day cruise ship:

October 18- 7 day leaves

October 25- 7 day returns

October 26- 7 day leaves again

November 2- 7 returns

November 3- 7 leaves again

November 10- 7 returns

November 11- 7 leaves again

November 18- 7 returns

November 19- 7 leaves again

November 26- 7 returns

November 27- 7 leaves again

December 4- 7 returns

December 5- 7 leaves again

December 12- 7 returns

December 13-7 leaves again

Author & Contact
Pam Joseph
prj1@aol.com