What is a data table?
A data table is an organized way to display information using rows and columns. Tables help us compare, count, and understand different sets of information quickly.
| Fruit | Number of Students |
|---|---|
| Apple | 8 |
| Banana | 5 |
| Orange | 7 |
| Grapes | 6 |
A table's title (caption) tells you what information the table contains. Always read the title first to understand what the data represents.
How to read a table
To read a table, identify the categories in the columns and the items in the rows. Find where a row and column meet to get specific information.
| Day | Picture Books | Chapter Books | Total Books |
|---|---|---|---|
| Monday | 12 | 9 | 21 |
| Tuesday | 15 | 11 | 26 |
| Wednesday | 10 | 14 | 24 |
To find how many picture books were checked out on Tuesday:
- Find the "Tuesday" row
- Follow across to the "Picture Books" column
- The answer is 15 picture books
Tables often include a "Total" column or row that adds up all the numbers. Check if the totals match when you add them yourself.
Comparing information in tables
Tables make it easy to compare different pieces of information by looking at numbers side by side.
| Friend's Name | Amount Saved |
|---|---|
| Marcus | $12.50 |
| Jasmine | $18.75 |
| Carlos | $15.00 |
| Sophia | $22.25 |
From this table we can compare:
- Sophia saved the most money: $22.25
- Marcus saved the least money: $12.50
- Jasmine saved $3.75 more than Carlos
When comparing money amounts in a table, always look at the decimal point. The digits to the left are dollars, and the digits to the right are cents.
Finding totals and differences in tables
Tables often require us to add or subtract numbers to find totals or differences between values.
| Item | Price | Number Sold | Total Value |
|---|---|---|---|
| Pencil Pack | $1.25 | 24 | $30.00 |
| Notebook | $2.50 | 18 | $45.00 |
| Eraser | $0.75 | 32 | $24.00 |
| Marker Set | $3.50 | 12 | $42.00 |
| Totals | 86 | $141.00 |
From this table we can calculate:
- Total items sold: 24 + 18 + 32 + 12 = 86 items
- Difference in sales between most and least expensive item: $45.00 - $24.00 = $21.00
- If we sold 10 more marker sets: 12 + 10 = 22 marker sets
When adding money in a table, line up the decimal points. This ensures you add dollars to dollars and cents to cents correctly.
Using tables to solve money problems
Tables help organize money information so we can solve problems about spending, saving, and comparing costs.
| Week | Allowance Earned | Money Spent | Money Saved |
|---|---|---|---|
| Week 1 | $8.00 | $3.50 | $4.50 |
| Week 2 | $8.00 | $2.75 | $5.25 |
| Week 3 | $8.00 | $4.25 | $3.75 |
| Week 4 | $8.00 | $1.50 | $6.50 |
Using this table, we can solve problems like:
- How much did Jacob earn in total? $8.00 × 4 = $32.00
- How much more did he save in Week 4 than Week 3? $6.50 - $3.75 = $2.75
- Could Jacob buy a $15.00 game after 4 weeks? Yes, he saved $4.50 + $5.25 + $3.75 + $6.50 = $20.00 total
When solving money problems with tables, always include the dollar sign ($) and decimal point in your answers. Write money amounts like this: $5.25 not 5.25 or 525.