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My True Love Sent to Me?

The Twelve Days of Christmas On the first day of Christmas my true love sent to me, A partridge in a pear tree. On the second day of Christmas my true love sent to me, Two turtle doves, And a partridge in a pear tree. On the third day of Christmas my true love sent to me, Three French hens, Two Turtle doves, And a partridge in a pear tree On the third day of Christmas my true love sent to me, Three French hens, Two Turtle doves, And a partridge in a pear tree.....Four calling birds… …Five golden rings… …. Six geese a-laying… ….Seven swans a-swimming… ….Eight maids a-milking… ….Nine ladies dancing… ….Ten lords a-leaping…. ….Eleven pipers piping… ….Twelve drummers drumming… Day 1 Presents 1 Day 2 Presents 3 Day 3 Presents 6 Day 4 Presents 10 Day 5 Presents 15 How many presents were sent: (a) On the 12 th day? (b) In total? Click to start music

DayPresentsTotal DayPresentsTotal Triangular Numbers ? Numbers Tetrahedral Numbers Stacking the triangular numbers one on top of the other gives: Make a table to help you calculate the number of presents given on the 12 th day and the number of presents given in total.

Pascal’s Triangle Pascal’s Triangle Blaisé Pascal ( ) Triangular Numbers Tetrahedral Numbers Natural/Counting Numbers You may be familiar with Pascal’s triangle from Algebra. The triangle shows triangular and tetrahedral numbers. You may also be familiar with the formula for the n th triangular number. There is also a very nice formula for calculating the n th tetrahedral number.

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Worksheet DayPresentsTotal DayPresentsTotal