Warehouse A stores 100 tons of grain, and Warehouse B stores 80 tons of grain. Warehouse A transports a batch of grain to Warehouse B. At this time, the grain in Warehouse A happens to be in Warehouse B (4/5). How many tons of grain did Warehouse A transport to Warehouse B?
甲仓库存粮食100吨，乙仓库存粮食80吨，甲仓库运了一批粮食到乙仓库，这时甲仓库的粮食正好是乙仓库的(4/5)．甲仓库运了多少吨粮食到乙仓库？
<gadget id="calculator">100 + 80</gadget>
<output>180</output>

<gadget id="calculator">4 + 5</gadget>
<output>9</output>

<gadget id="calculator">4 / 9</gadget>
<output>4/9 = around 0.444444</output>

<gadget id="calculator">180 * (4/9)</gadget>
<output>80</output>

<gadget id="calculator">100 - 80</gadget>
<output>20</output>

<result>20</result>