Xiao Ming plans to hire several identical robots to help him paint the walls of a room with an area of 18 square meters. After calculation, if he hires 12 robots, it will take 3 hours to complete all the painting of the walls. If Xiao Ming hires 4 robots to work How many square meters of room walls can be painted in 150 minutes?
小明打算雇佣若干个一模一样的机器人帮他粉刷面积为18平方米的房间墙面，经过计算，如果雇佣12个机器人，需要3个小时才能完成所有的墙面的粉刷，如果小明雇佣4个机器人工作150分钟，能粉刷多少平方米的房间墙面．
<gadget id="calculator">18 / 3 / 12</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(1/2) * 4 * 2.5</gadget>
<output>5</output>

<result>5</result>