Printer A can print 30 pages per minute. Printer B can print 40 pages per minute. Printer B begins printing 3 minutes after Printer A begins printing. Both printers stop printing 10 minutes after Printer A started. Together, how many pages did the two printers print?

Printer A prints for 10 minutes, so prints

... (30 pages/minute) * (10 minutes) = 300 pages

Printer B prints for 7 minutes, so prints

... (40 pages/minute) * (7 minutes) = 280 pages

At the end of 10 minutes, the two printers will have printed

... 300 pages + 280 pages = 580 pages