Question

Thirty-five samples of size 7 each were taken from a fertilizer-bag-filling machine. The results were: Overall mean = 54.75 lb.; Average range R = 1.54 lb.

a.) For the given sample size, the control limits for 3-sigma x chart are:

     Upper Control Limit (UCL = _____lb. (round your response to three decimal places).

     Lower Control Limit (LCL- ) = ______lb. (round your response to three decimal places).

b.) The control limits for the 3-sigma R-chart are:

      Upper Control Limit (UCLR) = ___ lb. (round your response to three decimal places).