A road construction team builds 80 meters of road every day. After 18 days of repairing, there are 560 meters left to be repaired. If the road is completed in 40 days, how many meters will be repaired less than before.
某修路队每天修路80米，修了18天后，还剩560米没修，若这条路40天修完，则每天比原来少修多少米．
<gadget id="calculator">80 * 18</gadget>
<output>1_440</output>

<gadget id="calculator">1_440 + 560</gadget>
<output>2_000</output>

<gadget id="calculator">2_000 / 40</gadget>
<output>50</output>

<gadget id="calculator">80 - 50</gadget>
<output>30</output>

<result>30</result>