Population and Size Detectives

Little Thunder had a question that wouldn't go away. "Which country is the biggest?"

"Biggest how?" asked Suzy. "Biggest land, or the most people?"

"Isn't that the same thing?"

Spike pulled out the farm's atlas. "Let's find out. We'll be detectives."

They chose five countries where the capital cows came from: Russia, Canada, Australia, India and Japan. Suzy cut paper strips for a bar chart, one strip for each country's land area.

Russia's strip was so long it hung off the table. Canada was next. Then Australia.

"Australia is huge!" said Little Thunder.

India was shorter, and Japan's strip was tiny.

"Now people," said Spike. He read the population numbers, and Suzy made a second chart.

This time, India's strip was the longest by far. Russia was much shorter. Japan was taller than Australia, even though its land strip was so tiny.

Little Thunder stared at the two charts. "Australia has loads of land but not many people. Japan has a little land and lots of people."

"So which is more crowded?" asked Suzy.

"That's called population density," said Spike. "How many people for each square kilometre of land. You divide people by area."

They did the sums together. Australia had only about three people for every square kilometre. Japan had more than three hundred.

"That's why there are so many paddocks here," said Little Thunder, "and so many tall buildings in Tokyo."

Tokyo the cow, who was resting by the trough, nodded. "At home, we live close together. Here, I can walk all day and only meet a kangaroo."

Little Thunder smiled. "So the biggest country isn't the busiest."

"Exactly, detective," said Suzy.