If the ending balance is $59,000, and this is increased by $11,000 over last year, then the beginning balance is $59,000 - $11,000 = $48,000. Add to the beginning amount the supplies purchased: $48,000 + $260,000 = $308,000. Again, since the ending balance is $59,000, we subtract this to get the difference, which will equal the expenses for the year: $308,000 - $59,000 = $249,000.