It’s summer vacation, and Xiao Ming went to his grandma’s house to play. After going uphill and downhill, it took 9 minutes to walk 300 meters uphill, and 6 minutes to walk downhill, with an average of 900 meters per minute. How many meters per minute is the average walking up and downhill?
放暑假了，小明去奶奶家玩，经过了一段上坡和下坡的路，上坡用了9分钟走了300米，下坡走了6分钟，平均每分钟走900米，小明走这段上下坡路的平均每分钟走多少米？
<gadget id="calculator">300 * 9</gadget>
<output>2_700</output>

<gadget id="calculator">900 * 6</gadget>
<output>5_400</output>

<gadget id="calculator">2_700 + 5_400</gadget>
<output>8_100</output>

<gadget id="calculator">9 + 6</gadget>
<output>15</output>

<gadget id="calculator">8_100 / 15</gadget>
<output>540</output>

<result>540</result>