Xiao Cong, Xiao Ming and Xiao Hao all go from A to B. One hour after Xiao Cong started, Xiao Ming set off again, and one hour after Xiao Ming set off, Xiao Hao started. It is also known that Xiao Cong travels 5 kilometers per hour, and Xiao Ming travels 4 kilometers per hour. Eleven hours after Xiao Ming set off, Xiao Cong and Xiao Hao arrived at B at the same time. How many hours did Xiao Hao catch up with Xiao Ming after he set off?
小聪、小明和小浩三人都从甲地到乙地，小聪出发后1小时，小明再出发，小明出发1小时后，小浩才出发．又知小聪每小时行5千米，小明每小时行4千米．小明出发后11小时，小聪和小浩同时到达乙地．小浩出发后多少小时追上小明．
<gadget id="calculator">11 + 1</gadget>
<output>12</output>

<gadget id="calculator">11 - 1</gadget>
<output>10</output>

<gadget id="calculator">12 / 10</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">5 * (6/5)</gadget>
<output>6</output>

<gadget id="calculator">6 - 4</gadget>
<output>2</output>

<gadget id="calculator">4 / 2</gadget>
<output>2</output>

<result>2</result>