Aunt Wang can make 100 velvet flowers every day. It takes Aunt Zhang 5 days to make the flowers that Aunt Wang made in 4 days. Aunt Zhang needs to make 1280 flowers.
王阿姨每天能做100朵绒花，王阿姨4天做的花张阿姨要5天才能做好，张阿姨要做1280朵花，几天才能做好？
<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">100 * (4/5)</gadget>
<output>80</output>

<gadget id="calculator">1_280 / 80</gadget>
<output>16</output>

<result>16</result>