Each unit of petroleum produced requires an input of 0.1 units of petroleum, so of the 900 units produced, (0.1*900) or 90 units of petroleum are required; each unit of textiles produced requires an input of 0.4 units of petroleum, so of the 300 units produced, (0.4*300) or 120 units of petroleum are required; each unit of transportation produced requires an input of 0.6 units of petroleum, so of the 850 units produced, (0.6*850) or 510 units of petroleum are required; and, each unit of chemicals produced requires an input of 0.2 units of petroleum, so of the 800 units produced, (0.2*800) or 160 units of petroleum are required. A total of 880 (90+120+510+160) dollars of petroleum are needed as input (internally consumed) to produce 900, 300, 850, and 800 million dollars of petroleum, textiles, transportation, and chemicals, respectively. Notice that the totals needed for input of petroleum, textiles, transportation, and chemicals can be found by multiplying the technology matrix times the production matrix.