In the "Giving Love" activity, the fourth grade donated 1980 yuan, which is 140 yuan less than the fifth grade. The total donation of the first, second and third grades is half of that of the fourth and fifth grades. How much is the total donation of the first, second and third grades?
在"献爱心"活动中，四年级捐款1980元，比五年级少140元，一、二、三年级共捐款数是四、五年级的一半，一、二、三年级共捐款多少元？
<gadget id="calculator">1_980 + 140 + 1_980</gadget>
<output>4_100</output>

<gadget id="calculator">4_100 / 2</gadget>
<output>2_050</output>

<result>2_050</result>