Xiao Ming types 80 words per minute, how many words can he type from 8:30 to 9:50 in the morning.
小明每分钟打字80个，从早上8：30到9：50能打多少个字．
<gadget id="calculator">80 * 80</gadget>
<output>6_400</output>

<result>6_400</result>