Question

Consider an order handling process with different causes of errors and the corresponding
frequencies as in the table below.

Cause of errors	Frequency of resulting errors
Browser error	18
Order number out of sequence	14
Products shipped, but credit card not billed	28
Order entry mistake	21
Products shipped to billing address, not shipping address	12
Wrong model shipped	57

(a)[1] Sort the frequencies from the highest to the lowest values.
(b)[1] Calculate percentages and cumulative percentages. (1 decimal, e.g. 23.4%)
(c)[1] Manually draw a Pareto diagram of the percentages, which includes a percentage ogive.
2
(d)[1] What cause(s) of errors the company should focus on.
(e)[1] Use Excel to draw a Pareto diagram of the percentages with a percentage ogive

Answer 1

a)

Cause of errors	Frequency of resulting errors
Wrong model shipped	57
Products shipped, but credit card not billed	28
Order entry mistake	21
Browser error	18
Order number out of sequence	14
Products shipped to billing address, not shipping address	12

b) % = Frequency of individual item/Sum of frequency of all items

Cumulative % = Sum of % values of item

Cause of errors	Frequency of resulting errors	Percentage	Cumulative Percentage
Wrong model shipped	57	38%	38%
Products shipped, but credit card not billed	28	19%	57%
Order entry mistake	21	14%	71%
Browser error	18	12%	83%
Order number out of sequence	14	9%	92%
Products shipped to billing address, not shipping address	12	8%	100%

c) Pareto:

d) Company should focus on top two issues which are the causes of 57% error which are Wrong model shipped and Products shipped but credit card not billed