15. The machines in a factory were classified according to the observed degree of defectiveness over the previous year's operations, as in the following table: Number of Machines % defective Cutting Grinding Millers machine machine 1% or less 22 74 102 Over 1% and less than 2% 31 102 143 2% and more 7 64 55 Is there any evidence to show a significant association between degree of defectiveness and type of machine? (use a = 0.02)