The school library subscribes to 83 kinds of science and technology books and fairy tale books, including 38 kinds of science and technology books. How many fewer subscriptions are science books than fairy tale books?
学校图书室订阅科技书和童话书共83种，其中科技书38种．科技书比童话书少订阅多少种？
<gadget id="calculator">83 - 38 - 38</gadget>
<output>7</output>

<result>7</result>