A 56-year-old male is burned while sleeping in his home. His right upper and lower extremity and the anterior aspect of the upper chest have extensive second-degree burns.The extent of the burn is calculated to represent what percentage of body surface area?Relative Percentages of Areas Affected by GrowthAreaAge1015Adult A = half of head512412312B = half of one thigh414412434Relative Percentages of Areas Affected by GrowthAreaAge015A = half of head912812612B = half of one thigh2343144Table for estimating extent of burns. In adults, a reasonable system for calculating the percentage of body surface burned is the "rule of nines"--Each arm equals 9%, the head equals 9%, the anterior and posterior trunk each equals 18%, and each leg equals 18%; the sum of these percentages is 99%