Lesson 2 of 8 · Grades 3 to 5
Reading tables
A table keeps data tidy. Every row and every column has a label, and the number you want sits in the cell where the row and the column meet.
A table keeps data tidy
A tally chart is good while you are collecting data. A table is good when you want to look at the data later, because it puts every number in its own place. Rows run across, columns run down, and the place where one row meets one column is called a cell.
Every row and every column has a label. The label tells you what the row or column means, so a table can hold much more detail than a tally chart without becoming confusing.
Finding one number
This table shows a fruit vote in two classes. The first column names the fruit, and the next two columns hold the votes for class 3A and class 3B.
| Fruit | Class 3A | Class 3B |
|---|---|---|
| Apple | 8 | 6 |
| Banana | 5 | 7 |
| Cherry | 4 | 3 |
| Grape | 2 | 5 |
To read one number, find the row first, then move across to the column. Apples in class 3B: find the Apple row, follow it across to the Class 3B column, and read 6. Grape in class 3A: find the Grape row and read 2. Every bigger graph skill starts here.
Reading a whole row
A row tells one story. The Banana row says that bananas got 5 votes in class 3A and 7 votes in class 3B. Add the two cells and the fruit got 12 votes altogether. The Apple row gives 8 + 6 = 14 votes, so apples beat bananas by just 2 votes.
A column tells a different story. The Class 3A column says that class 3A gave 8 apple votes, 5 banana votes, 4 cherry votes and 2 grape votes. The class made 8 + 5 + 4 + 2 = 19 votes in total. The Class 3B column adds up to 6 + 7 + 3 + 5 = 21 votes.
A table with two sets of people
Tables can compare groups too. This one shows how children travel to school. The rows are girls and boys, and the columns are walking, bus and car.
| Walk | Bus | Car | |
|---|---|---|---|
| Girls | 5 | 4 | 3 |
| Boys | 6 | 2 | 4 |
The Girls row meets the Bus column at 4, so 4 girls take the bus. The Boys row meets the same column at 2, so 2 boys take the bus. Together, 4 + 2 = 6 children travel by bus. Walking is the most popular way for both groups: 5 + 6 = 11 children walk.
Totals and missing cells
Some tables add a Total column or a Total row. Use it to check your work: if the parts add up to something different from the printed total, look again. A table can also help you find a missing number. If a row total is 9, the morning cell is 2 and the afternoon cell is missing, then the afternoon cell must be 9 − 2 = 7, because the two parts must add to the total.
Worked example
The table shows books read in a week. Monday is 3 in the morning and 2 in the afternoon, Tuesday is 5 and 1, and Wednesday is 2 and 6. How many books were read on Wednesday?
Step 1: find the Wednesday row. The row label is on the left.
Step 2: read the two cells in that row. Morning is 2 and afternoon is 6.
Step 3: add the cells to get the row total. 2 + 6 = 8.
Step 4: check with the Total column of the table. It should also say 8.
Answer: 8 books on Wednesday.
Watch out for this
Do not add numbers from different columns by mistake. The 5 in the Banana row and the 5 in the Grape row are both votes, so they can be added. But the row and the column labels keep each number in its place: always name the row and the column when you read a cell.
Remember
- A cell is where one row and one column meet.
- Find the row first, then move across to the column.
- Add a row to get that row's total, and add a column to get that column's total.
- Use a printed total to check your work, or to find a missing cell.
Try it
Answer the five questions below. Work them out first, then open each answer to check.
-
In the table, apples got 8 votes in class 3A and 6 votes in class 3B. How many votes did apples get in class 3B?
Show answer
6 votes. Follow the Apple row across to the 3B column.
-
Bananas got 5 votes in 3A and 7 votes in 3B. How many more votes did bananas get in 3B?
Show answer
2 votes. 7 - 5 = 2.
-
Grapes got 2 votes in 3A and 5 votes in 3B. What is the total for grapes?
Show answer
7 votes. 2 + 5 = 7.
-
In class 3A, apples got 8 votes, bananas 5, cherries 4 and grapes 2. How many fruits got more than 5 votes?
Show answer
1 fruit. Only apples got more than 5 votes.
-
Class 3A got 8 apple votes, 5 banana votes, 4 cherry votes and 2 grape votes. How many votes did class 3A get altogether?
Show answer
19 votes. 8 + 5 + 4 + 2 = 19.
Puzzle · Table detective
Puzzle time
The table shows the books read by class 4B in one week. Wednesday is the only day with a hidden cell, and its row total is 9. How many books were read on Wednesday afternoon?
Show a hint
The morning cell and the afternoon cell must add up to the row total.
Show the answer
Answer: 5. The Wednesday row total is 9 and the morning cell is 4. The afternoon cell is 9 - 4 = 5 books.