Dongdong has read a 250-page book, and the number of pages she has read is 50 more than the number of pages she has not read. How many pages has Dongdong read?
冬冬看了一页250页的书，已经看的页数比未看的页数多50页，冬冬看了多少页？
<gadget id="calculator">250 + 50</gadget>
<output>300</output>

<gadget id="calculator">300 / 2</gadget>
<output>150</output>

<result>150</result>