Answer
There are approximately $350 million$ more Internet users in China than in Germany.
Work Step by Step
The question asks to compare. So we need to approximate the number of Internet users in both China and Germany and then we could compare these two values.
The China bar goes almost half the way from 400 million to 450 million, so we would approximate there are 425 million Internet users in China.
The Germany bar also goes almost half the way from 50 to 100 million, so we would approximate there are 75 million Internet users in Germany in 2010.
Therefore there are approximately $425-75=350 million$ more Internet users in China than in Germany.
