Reading and Interpreting Data

A graph is just a picture of numbers. Once you can read the picture, those "tricky" data questions turn into easy marks — because the answer is already sitting there on the page, waiting for you to find it. In this note you'll learn to read every kind of chart the PSLE loves: tables, bar graphs, line graphs and pie charts.

Parents: ask your child to predict the answer before they reveal each step. The blue dotted words are tappable definitions, and the "Method tip" boxes name exactly what a marker rewards — reading off the correct axis or the matching slice.

By the end you'll be able to read a value off any chart, compare data to find the biggest, smallest and difference, read line graphs and pie charts, and use data to solve word problems. Let's read some pictures.

Reading a table

A table is the simplest way to store data. To read it, find the row and column you need, then read where they meet.

Say a table shows how many books four pupils read in a month: Amir 8, Bina 12, Chen 5, Dina 15. To answer "How many books did Bina read?" you find Bina's row and read across — 12. To answer "How many books in total?" you add every value: 8 + 12 + 5 + 15 = 40. The trick is to read slowly and match the exact name to the exact number.

Reading a bar graph

A bar graph shows amounts as bars. The taller the bar, the bigger the amount. To read one, look across from the top of the bar to the number on the vertical axis (the side scale).

The most important step is the scale. If each gridline goes up by 5, a bar that reaches the third line is worth 15, not 3. Always check what one step is worth before you read any bar.

Reading a line graph

A line graph shows how a value changes — usually over time. The line going up means the value is increasing; going down means decreasing; flat means it stays the same.

To read a line graph, go up from the time on the bottom, stop at the line, then read across to the side scale. To find a change, read the value at the start and at the end and subtract. The steepest part of the line is where the value changed the fastest.

Reading a pie chart

A pie chart shows how a whole is divided into parts. A bigger slice means a bigger share. The whole circle is everything together — the total.

Often a slice is given as a fraction of the whole. If a pie chart of 200 pupils shows that one quarter chose swimming, then swimming = one quarter of 200 = 200 ÷ 4 = 50 pupils. To find a slice, work out its fraction of the total. To find the total from a slice, you may need to add all the slices.

Watch out — these are easily mixed up

Quick recap

🎯 Mastery check

Answer all 6 — your progress is saved on this device.

1. A table shows ice creams sold: Mon 14, Tue 9, Wed 20, Thu 11. How many were sold in total?

   544434

2. On a bar graph the scale goes up in steps of 10. A bar reaches the 5th line above zero. What value does it show?

   51550

3. A line graph shows the temperature was 18 degrees at 9am and 27 degrees at noon. By how much did it rise?

   9 degrees45 degrees27 degrees

4. A pie chart shows 300 stickers in a box. One third are gold. How many gold stickers are there?

   100150900

5. A bar graph shows Class A scored 35 points and Class B scored 50 points. How many more points did Class B score?

   158550

6. A pie chart shows 80 drinks. Half are juice and one quarter are milk. How many drinks are NEITHER juice nor milk?

   204060

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