Xiaofang and Xiaohong walk towards each other from two places 600 meters apart at the same time. Xiaofang walks 45 meters per minute. After 7 minutes, the two pass each other and the distance is 100 meters. How many meters does Xiaohong walk per minute?
小芳和小红同时从相距600米的两地相对走来，小芳每分钟走45米，经过7分钟后二人擦肩而过又相距100米，小红每分钟走多少米？
<gadget id="calculator">600 + 100</gadget>
<output>700</output>

<gadget id="calculator">700 / 7</gadget>
<output>100</output>

<gadget id="calculator">100 - 45</gadget>
<output>55</output>

<result>55</result>