In printing an article of 21,000 words, a printer decides to use two sizes of type. Using the larger type, a printed page contains 1,200 words. Using the smaller type, a page contains 1,500 words. The article is allotted 16 full pages in the magazine. How many pages must be in the larger type?

The article is allotted 16 full pages in the magazine, so the total number of words that can fit on the 16 pages is 16 x 1,500 = 24,000 words. Since the article is 21,000 words, the remaining 3,000 words must fit on the remaining 3 pages. Since the larger type contains 1,200 words per page, 3 pages in the larger type will fit 3 x 1,200 = 3,600 words. Therefore, 3 pages must be in the larger type.