12 Days of Christmas (1/4/10 - 1/7/10)

The song, the 12 Days of Christmas, is a fun (albeit repetitive) song about the gifts given to "My True Love" on the 12 days of Christmas between the birth of Jesus Christ and the Epiphany, January 6th, the day Christians celebrate the arrival of the Magi (Wise Men).  The Mathletes had fun singing this tune, but where is the math?

For the past 26 years, a financial services company called PNC has calculated the cost of the items if purchased at current prices.  Over the years, trends have emerged and the Christmas Price Index (CPI) has often increased or decreased at a rate consistent with the other CPI, the Consumer Price Index, a measure of inflation produced by the U.S. Department of Labor. Showcasing the cost of items from a partridge to drummers, the Christmas Price Index is a fun way for students, children and adults to measure consumer spending and trends in the economy.

I had the students add the years 1984 and 2009 to see what has happened to prices over time.  The challenge for the week is for them to add up as many of the other years as possible.  They will receive 5 Mathlete Dollars for each year.

The attached excel spreadsheets have each years costs with and without answers.

The younger Mathletes (1st and 2nd grade) should try this by disregarding the cents and the older Mathletes (3rd, 4th and 5th grade) should try this including the cents. Remember to bring the decimal down to the answer.

The oldest Mathletes were also asked to think about the cost of each item by dividing the cost by the number of items (the easiest example was the seven swans in 1984 at a total cost of $7,000 or $1000 per swan). 

Although, I am Jewish, I have limited training in Theology at my two Jesuit institutions, Georgetown and Boston College Law.  For some of the parents, you may have interest in the religious symbolism and history of the song.  None of this has been verified by primary sources, yet in the mid-16th century in England, it seems plausible. Read on:


The Christmas song, "The Twelve Days of Christmas" may sound silly and contrived to many of us. But it actually had its origins in religious symbolism - and with a serious purpose.
   It dates from a time of religious persecution. The song, "The Twelve Days of Christmas," was written as a kind of secret catechism that could sing in public without fear of arrest - a learning or memory aid to Christians in fact.
   The song can be taken at two levels of interpretation - the surface meaning, or the hidden meaning known only to the Christians involved. Each element is a code word for a religious truth.

1. The partridge in a pear tree is Jesus.

2. The two turtledoves are the Old and New Testaments.

3. Three French hens stand for faith, hope and love.

4. The four calling birds are the four Gospels.

5. The five gold rings recall the Hebrew Torah (Law), or the Pentateuch, the first five books of the Old Testament.

6. The six geese a-laying stand for the six days of creation.

7. The seven swans a-swimming represent the seven gifts of the Holy Spirit.

8. The eight maids a-milking are the eight Beatitudes.

9. Nine ladies dancing are the nine fruits of the Holy Spirit.

10. The ten lords a-leaping are the Ten Commandments.

11. Eleven pipers piping represent the eleven faithful Apostles.

12. Twelve drummers drumming symbolize the twelve points of doctrine in the Apostles Creed.

PNC_Christmas_Price_Index_Historical_Data.xls19.5 KB
PNC_Christmas_Price_Index_Historical_DataAnswers.xls19.5 KB