There are 120 people in the first workshop and 450 kg of grain for 5 days. The second workshop has 250 people and currently has 750 kg of grain. Calculated according to the grain consumption of the first workshop, how many kilograms of grain must be allocated to the second workshop for 7 days?
第一车间有120人，5天用粮450千克．第二车间有250人，目前有粮食750千克．照一车间用粮情况推算，二车间吃7天，还必须再拨给他们粮食多少千克？
<gadget id="calculator">450 / 5 / 120</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">250 * 7 * (3/4)</gadget>
<output>2_625/2 = around 1_312.5</output>

<gadget id="calculator">(2_625/2) - 750</gadget>
<output>1_125/2 = around 562.5</output>

<result>1_125/2 = around 562.5</result>