The school has newly purchased a batch of books, including 250 story books, and more science books than story books (3/10). How many science books have been purchased?
学校新购入一批图书，故事书250本，科技书比故事书多(3/10)，购入科技书多少本？
<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">250 * (3/10)</gadget>
<output>75</output>

<gadget id="calculator">75 + 250</gadget>
<output>325</output>

<result>325</result>