# Lesson 8

Spreadsheet Shortcuts

Let's explore recursive formulas in spreadsheets.

### Problem 1

*Technology required.* Open a blank spreadsheet. Use "fill down" to recreate this table of equivalent ratios. You should not need to type anything in rows 3–10.

### Problem 2

A list of numbers is made with the pattern: Start with 11, and subtract 4 to find the next number.

Here is the beginning of the list: 11, 7, 3, . . .

Explain how you could use "fill down" in a spreadsheet to find the tenth number in this list. (You do *not *need to actually find this number.)

### Problem 3

Here is a spreadsheet showing the computations for a different version of the birthday trick:

Explain what formulas you would enter is cells B4 through B8 so that cell B8 shows a number representing the month and day. (In this example, cell B8 should show 704.) If you have access to a spreadsheet, try your formulas with a month and day to see whether it works.

### Problem 4

Write a formula you could type into a spreadsheet to compute the value of each expression.

- \(\frac25\) of 35
- \(25 \div \frac53\)
- \(\left( \frac{1}{11} \right) ^ 4\)
- The average of 0, 3, and 17

### Problem 5

The data set represents the number of cars in a town given a speeding ticket each day for 10 days.

- 2
- 4
- 5
- 5
- 7
- 7
- 8
- 8
- 8
- 12

- What is the median? Interpret this value in the situation.
- What is the IQR?

### Problem 6

The data set represents the most recent sale price, in thousands of dollars, of ten homes on a street.

- 85
- 91
- 93
- 99
- 99
- 99
- 102
- 108
- 110
- 115

- What is the mean?
- What is the MAD?