Each day for two work weeks (10 days total), George weighs 4 bags from that day's production. If the average of the means is 14 oz. and the average range is 0.4 oz., what is the lower control limit for an x-bar chart for this process?

Question

Saul

Social Studies

25 April, 13:23

Each day for two work weeks (10 days total), George weighs 4 bags from that day's production. If the average of the means is 14 oz. and the average range is 0.4 oz., what is the lower control limit for an x-bar chart for this process?

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Answers (1)

Know the Answer?

Chaim Alvarez · Answer 1

Answer: 13.7084

Explanation:

Given the following;

Average of means = 14 oz

Average range = 4 oz

Subgroup size = 4

The Lower Control Limit (LCL) of an x-bar chart is calculated using the relation:

LCL = average mean + (A2 * average range)

A2 is an x - bar constant which varies depending on the number of subgroups given.

A2 for a Subgroup of 4 for an x-bar chart is 0.729

LCL = 14 - (0.729 * 0.4)

LCL = 14 - 0.2916

LCL = 13.7084