[list][*]In cell B4, we want to enter = B1 * 5 to multiply the month by 5. Enter this, but when you are about to type B1, instead, click on cell B1. This shortcut can be used any time: click on a cell instead of typing its address.[/*][/list][list][*]Practice this technique as you program each cell in B5 through B10 to perform the right computation.[/*][*]When you are finished, does cell B10 show a number that contains the month and day of your birthday? If not, troubleshoot your computations.[/*][/list][list][*]Try changing the month and day in cells B1 and B2. The rest of the computations should automatically update. If not, troubleshoot your computations.[/*][/list]

Why does this trick work? Try using [math]m[/math] for the month and [math]d[/math] or the day, and writing the entire computation as an algebraic expression. Can you see why the resulting number contains the month and day?

[list][*]Use spreadsheet calculations to continue the patterns in columns A and B, down to row 5. Pause for discussion.[/*][/list][list][*]Click on cell A5. See the tiny blue square in the bottom right corner of the cell? Click it and drag it down for several cells and let go.[/*][*]Repeat this, starting with cell B5.[/*][/list]