The little rabbit can pick mushrooms. It can pick 40 mushrooms a day in sunny days, but it can only pick 24 mushrooms in rainy days. It picks 224 mushrooms in a few days, with an average of 28 mushrooms a day. How many of these days are rainy days?
小兔子采蘑菇，晴天每天能采40只，雨天每天只能采24只，它一连几天共采了224只蘑菇，平均每天采28只，这些天中有多少天是下雨天．
<gadget id="calculator">224 / 28</gadget>
<output>8</output>

<gadget id="calculator">40 * 8</gadget>
<output>320</output>

<gadget id="calculator">320 - 224</gadget>
<output>96</output>

<gadget id="calculator">40 - 24</gadget>
<output>16</output>

<gadget id="calculator">96 / 16</gadget>
<output>6</output>

<result>6</result>