In a town, there are four primary schools. Two of them can teach 400 students at a time, and the other two 340 students at a time. How many students at a time in total, can these four primary schools teach?
Two schools can teach 400 students, so in total, they can teach 2 * 400 = 
<gadget id="calculator">2*400</gadget>
<output>800</output>
800 students.
The other two schools can teach 340 students, which gives 2 * 340 = 
<gadget id="calculator">2*340</gadget>
<output>680</output>
680 students in total.
So all four schools can teach 800 + 680 = 
<gadget id="calculator">800+680</gadget>
<output>1_480</output>
1480 students at a time.

<result>1_480</result>