Reading data within tables and graphs is a great skill to develop because it helps you with everyday life (think about bus/train timetables), and also, it appears on some exams such as the 11 Plus, NSW Selective School, VIC selective school, scholarship exams and more.

Why is information sometimes put in a table (like below) or chart form (or both)? We’ll some information is easier to convey in that format compared to being written out.  For example, it’s easier to locate a train within a table format if you’re looking for a 9am train that reaches the city at 9:30am right?  Compared to reading it in an essay form (which would be really odd!)

Anyway, let’s go to the sample practice question…

The chart below records rainfall over this week’s weekdays (week 2) compared to last week. Use it to answer the question below.

What was the total increase in rainfall from this week compared to last week?

To answer this question, we need to first understand what it’s asking us.  This is so important because it helps you to understand what information you are to look for in the first place!

1) Understand what the question wants you to do & Formulate.

So it wants the total increase (so we’re looking at Monday - Friday) and compared from this week to last week.  So essentially we want the different between week 2 and week 1.  Easy peasy.  Now that I know what the question needs me to do, I just formulate.  The easiest way to do this is: sum totals of week 2 - sum of totals week 1.  **

2) Calculate & Get Solution

Using my formula: sum totals of week 2 - sum of totals week 1, I’ll now calculate.

(60+20+7+5+5) - (55+10+5+0+5) = 97 - 75 = 22

So the answer is 22mm.

Remember to include the mm and know how to convert mm (millimetres) to cm (centimetres) and other units of measurement.