CREATE TABLE table_16409745_1 (dpi VARCHAR, max_page_size VARCHAR)

What is the dpi for the scanner with a max page size of 216mm x 355mm?
SELECT dpi FROM table_16409745_1 WHERE max_page_size = "216mm x 355mm"
SELECT "dpi" FROM "table_16409745_1" WHERE "216mm x 355mm" = "max_page_size"