The weighted average unit cost for these purchases of inventory is 9.60. We will calculate it by multiplying the unit to per units and divide it to another. 200 * 9 = 1800, 300 * 10 = 3000
1800 divide by 3000 = .60.60 plus the original price per unit which is 9 = 9.60
9.60 is the answer in this question.