I wouldn't draw this example. You are told the MAC is 82 inches long, the CG is 14.7% of that distance back from the leading edge of the MAC, i.e. 14.7 x 82 / 100 = 12 inches back from the leading edge. The leading edge itself is 103 inches aft of the datum so the CG should be 103 + 12 = 115 inches aft.