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Statistical Quality Control is a famous statistical tool used to improve the quality of the products used by our society, and the control chart is one of the more common techniques for quality improvement. A Control chart for variables contains control limits, which are obtained by using standard estimation techniques. It is possible to assume that there exits an auxiliary variable related to variable of interest used to improve the quality of a give product. Assuming control chart for variables, we propose to obtain the control limits by using the information provided by an auxiliary variable