In Class 1 of the third grade, 25 people subscribed to "Fun Mathematics", 22 people subscribed to "Youth Science and Technology News", 9 people subscribed to both publications, and 10 people did not subscribe to both publications. Do you know how many of them there are?
三年级一班有25人订阅了《趣味数学》，22人订阅了《少年科技报》，有9人两种刊物都订阅了，还有10人两种刊物都没订阅．你知道他们有多少人吗？
<gadget id="calculator">22 - 9</gadget>
<output>13</output>

<gadget id="calculator">25 + 13 + 10</gadget>
<output>48</output>

<result>48</result>