The little cat Mimi caught 1 mouse on the first day, and every day thereafter caught 1 more mouse than the previous day. How many mice did Mimi catch in total in 10 days?
小猫咪咪第一天逮了1只老鼠，以后每天逮的老鼠都比前一天多1只，咪咪10天一共逮了多少只老鼠．
<gadget id="calculator">1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10</gadget>
<output>55</output>

<result>55</result>