bamboo shoot grows at a constant speed from germination to growth, and it can grow to 40 decimeters in 10 days. Then, how many days will it take to grow to 16 decimeters?
一根竹笋，从发芽到长大，匀速生长，经过10天可以长到40分米，那么，当长到16分米时经过多少天．
<gadget id="calculator">40 / 10</gadget>
<output>4</output>

<gadget id="calculator">16 / 4</gadget>
<output>4</output>

<result>4</result>