Use 10-meter-long steel bars as raw materials, and cut 100 steel bars each with a length of 3 meters and a length of 4 meters. How many raw materials should be used at least?
用10米长的钢筋做原材料，截取3米和4米长的钢筋各100根，至少要用多少根原材料？
<gadget id="calculator">100 / 2</gadget>
<output>50</output>

<gadget id="calculator">50 / 2</gadget>
<output>25</output>

<gadget id="calculator">50 + 25</gadget>
<output>75</output>

<result>75</result>