Computer Club

 

Kay started a computer club, and for a while she was the only member.  She planned to have each member find two new members each month.  By the end of the first month she had found two new members.  If her plan is carried out, how many members will the club have at the end of 6 months?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Twelve Days of Christmas

 

In the familiar song, “The twelve days of Christmas,” the total number of gifts received each day is a triangular number.  On the first day there was 1 gift, on the second day there were 3 gifts, on the third day 6 gifts, etc., until the 12th day of Christmas.

a. How many gifts were received on the 12th day?

b. What is the total number of gifts received during all 12 days?

 

 

 


Cactus Gardens

 

A gift shop chain in the Southwest presently sells miniature cactus gardens for $20 each.  It costs the chain $10 per garden for materials, assembling, and packaging.  The chain’s management is considering changing the price per garden to improve total profits from the gardens.  At the present price the chain sells 200/wk.  Marketing consultants have told the chain that for each decrease of $1 in the present selling price, the chain can sell 5 additional gardens above the 200.  Similarly, for each $ increase in the selling price, the chain will sell 5 gardens few than the 200.  (For example, at a price of $21 each, the chain will sell 195; at a price of $22 each, the chain will sell 190; and so on.)  Management wants to know whether it should raise or lower the selling price and by how much in order that it’s total income from the gardens will be as large as possible.

 

 

 

 

 

 

 

Voila!!

 

Complete this table and look for a pattern.

 

Sum                                        Answer

1                                              1

1+3                                         4

1+3+5                                                                 

1+3+5+7

1+3+5+7+9

 

How many odd whole numbers would have to be added to get a sum of 81?

How many odd whole numbers would have to be added to get a sum of 169?

What about a sum of 529??