the total marks obtained by a student in mathematics and physics is 90 and his score in chemistry is 30 marks more than that in physics . find the average marks scored in mathamatics and chemistry together .
"let the marks obtained by the student in mathematics , physics and chemistry be m , p and c respectively . given , m + c = 90 and c - p = 30 m + c / 2 = [ ( m + p ) + ( c - p ) ] / 2 = ( 90 + 30 ) / 2 = 60 . answer : e"
divide(add(90, 30), const_2)