GR Three Numbers Converter: Volume I - Questions - Addition

This is a mathematical book and you must find the addition of two numbers with the given hint and the addition. f.e. you have the question 1 : ( - 1 - ) + ( - 1 - ) = 828 (see first book Questions) and you have to find the answer 1 : 216 + 612 = 828 (see second book Solutions)