Red Apple Primary School donated stationery to the children in the disaster area. The third grade students donated 340 pieces, the fourth grade donated 80 less than the third grade, and the fifth grade donated four times as much as the fourth grade. How many pieces did the fifth grade donate?
红苹果小学为灾区小朋友捐赠文具，三年级同学捐了340件，四年级比三年级少捐了80件，五年级捐的件数是四年级的4倍，五年级捐了多少件？
<gadget id="calculator">340 - 80</gadget>
<output>260</output>

<gadget id="calculator">260 * 4</gadget>
<output>1_040</output>

<result>1_040</result>