Solving this equation we get: x (number of gold medals at the Vancouver Olympics) = 9 / 1.8 = 5. This means that at the 2010 Vancouver Winter Olympics, the Chinese delegation won a total of 5 gold medals.

　　At the Beijing Winter Olympics, the Chinese delegation performed well and won nine gold medals. For comparison, let's review the number of gold medals of the Chinese delegation at the 2010 Vancouver Winter Olympics. If we set the number of gold medals in the Beijing Winter Olympics as 9 and the target as x, we need to find out the number of gold medals in the Winter Olympics in previous years. Then there is the equation: 9 = 1.8x (the "×" symbol can be replaced with a text description: that is, China's nine gold medals are 1.8 times that of Vancouver).

• CBA