Consumer Packaging and Labelling Regulations (C.R.C., c. 417)

PART ISamples

PART IIFormula for Determining the Weighted Average Quantity of the Units in a Sample

For the purposes of paragraph 39(4)(a), the formula for adjusting the sample mean to determine the weighted average quantity of the units in the sample is as follows

where

X_a

is the weighted average quantity of the units in the sample

x

is the sample mean calculated as follows:

x = ∑x ÷ n

∑x

is the sum of the net quantities of all units in the sample

t

is the value determined in accordance with Part III for the selected sample size

n

is the number of units in the sample

s

is the standard deviation of the sample, calculated as follows

∑(x-x)²

is the sum of the squared differences between the sample mean and the net quantity of each unit in the sample.

• ^*The value of (t ÷ √n) may, instead of being calculated in accordance with this Part, be determined using the applicable value set out in Column III of the table to Part III

PART IIITable for Values of t and (t ÷ √n)

Column I	Column II	Column III
Sample Size	tFootnote for *	(t ÷ √n)Footnote for *
2	63.657	45.01	Linear Interpolation of Values Where a sample size is selected that is not listed in Column I of this table and lies between 32 and 125, the value of t will be determined by linear interpolation as follows: where a is the value of t for the closest sample size below the selected sample size b is the value of t for the closest sample size above the selected sample size c is the result of 120 divided by the closest sample size below the selected sample size d is the result of 120 divided by the closest sample size above the selected sample size e is the result of 120 divided by the selected sample size
3	9.925	5.73
4	5.841	2.92
5	4.604	2.06
6	4.032	1.65
7	3.707	1.40
8	3.499	1.24
9	3.355	1.12
10	3.250	1.03
11	3.169	0.955
12	3.106	0.897
13	3.055	0.847
14	3.012	0.805
15	2.977	0.769
16	2.947	0.737
17	2.921	0.708
18	2.898	0.683
19	2.878	0.660
20	2.861	0.640
21	2.845	0.621
22	2.831	0.604
23	2.819	0.588
24	2.807	0.573
25	2.797	0.559
26	2.787	0.547
27	2.779	0.535
28	2.771	0.524
29	2.763	0.513
30	2.756	0.503
31	2.750	0.494
32	2.746	0.485
64	2.657	0.332
96	2.634	0.269
125	2.615	0.234

• Return to footnote ^*Where all units in a lot are selected to constitute a sample, zero shall be used as the value of t and (t ÷ √n).

PART IVMinimum Number of Units for the Purposes of Paragraph 39(4)(B)

• Return to footnote ^*Minimum number of units in the sample that results in the lot not meeting the requirements of the Act and these Regulations respecting the declaration of net quantity.