IOWA CITY  Like an airline overselling a flight, the University of Iowa extended admission this year to several thousand more applicants than it could accommodate on campus in this fall’s freshman class.

While nearly every university overbooks each year, relying on sophisticated algorithms that predict just how many admitted students will probably go elsewhere, Iowa officials were surprised to learn this spring how far off they were in their math. This fall’s freshman class is likely to have more than 400 more students than last year’s, an unintended increase of about 10 percent, for a total of just over 4,500.

Though the university considers this a happy accident  much of the growth has come from outside Iowa, including from schools as far away as China and India, whose graduates typically pay triple the tuition of state residents  the looming flood of new students has left the university scrambling to figure out where they will sleep, and how to fit them into some of the most popular courses.

In anticipation of the students’ arrival, the university has been securing local apartment buildings and temporarily converting open dormitory lounges into private spaces that can accommodate as many as eight beds.