Xiaofang collected 10 sets of animal pictures, 5 pieces in each set, and gave 19 pieces to her classmates. How many pieces are left?
小芳收集了10套动物画片，每套5张，送给同学19张，还剩多少张？
<gadget id="calculator">5 * 10</gadget>
<output>50</output>

<gadget id="calculator">50 - 19</gadget>
<output>31</output>

<result>31</result>