The school bought 250 books, 40% of the total will be allocated to the first grade, and the rest will be distributed to the second and third grades at a ratio of 2:3. How many books does the third grade get?
学校买来250本图书，一年级分去总数的40%，其余的按2：3分给二年级和三年级．三年级分得图书多少本？
<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">250 * (3/5)</gadget>
<output>150</output>

<gadget id="calculator">2 + 3</gadget>
<output>5</output>

<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">150 * (3/5)</gadget>
<output>90</output>

<result>90</result>