Problem: the area of a rectangle is 360 sq . m . if its length is increased by 10 m and its width is decreased by 6 m , then its area does not change . find the perimeter of the original rectangle . 
Options: ['a ) 74 m', 'b ) 75 m', 'c ) 76 m', 'd ) 77 m', 'e ) 78 m']
c