Patti wrote to Ana and her students in Taiwan:
I would like my students (and you) to figure out how many hours apart we are. We are in Maryland and our GMT factor is -5. This means that we are five hours behind the time in the UK. What is your GMT factor? This will help us determine how many hours we are apart. The time stamp on your message tells me that you are GMT +8.
From: "Ana" firstname.lastname@example.org
To: "Patti Weeg" email@example.com
Subject: A short note from Taiwan
Date: Sat, 29 Nov 2003 15:51:40 +0800
I am going to ask my students if they can figure out the number of hours difference from this information and from our GMT factor. We will use a number line. GMT will be 0 on the line. We will put Maryland on -5 and Taiwan on +8. You can see the students doing this activity in the picture. Click on this link to download the Word file with this activity: GMT Activity Sheet
We can look here to confirm our math.
Here is a fun set of clocks and a world map: