A 20-percent increase in undergraduate tution has been proposed for the next school year at the University of Missouri. University officials say the increase will help offset big budget cuts made by the Legislature. The tuition increases would mean an in-state student taking 30 credit hours a year would pay almost $6,000. Out-of-state students would pay more than $1,500 for those 30 hours. The University of Missouri already is the most expensive public university in the state and one of the most expensive state universities in the midwest. The University jacked up tuition by 15 percent last this year. Curators are being asked to approve the increases when they meet Thursday and Friday.