APPENDIX IIMATHEMATICSThe purpose of this mathematics section is twofold:first, it is a refresher for the Steelworker who has en-countered a time lapse between his or her schooling inmathematics and the use of this subject in sheet metalwork; second, and more important, this section appliesmathematics to steelworking tasks that can not be ac-complished without the correct use of mathematicalequations.The mathematics problems described in this sectionare examples only and are not converted into the metricsystem. However, if you so desire, you can convert allof the problems by using the metric conversion tables inappendix 111 of this manual. If you need more informa-tion on metrics, order The Metric System, NAVEDTRA475-01-00-79, through your Educational Services Offi-cer (ESO)..LINEAR MEASUREMENTMeasurements in sheet metal are most often madein feet (ft) and inches (in.). It is necessary that a sheetmetal worker know how to make computations involv-ing feet and inches. In addition, it is necessary to becomefamiliar with the symbols and abbreviations used todesignate feet and inches, such as the following:12 inches = 1 foot; 12 in. = 1 ft; 12” = 1’CHANGING INCHES TOFEET AND INCHESTo change inches to feet and inches, divide inchesby 12. The quotient will be the number of feet, and theremainder will be inches.Example:CHANGING FEET ANDINCHES TO INCHESTo change feet and inches to inches, multiply thenumber of feet by 12 and add the number of inches. Theresult will be inches.Example:CHANGING INCHES TOFEET IN DECIMAL FORMTo change inches to feet in decimal form, divide thenumber of inches by 12 and carry the result to therequired number of places.Example:Answer: 9.67CHANGING FEET TO INCHESIN DECIMAL FORMTo change feet in decimal form to inches, multiplythe number of feet in decimal form by 12.Example;AII-1