APMFG Tally Table
Tally marks
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105.813

Step-by-step explanation:

Given that:

Mean (m) = 143 lb

Standard deviation (s) = 29 lb

. First decile which separate the 10th..

Using the relation :

Z = (x - mean) / standard deviation

The bottom 10% percentile using the Z probability calculator = - 1.282

-1.282 = (x - 143) / 29

-1.282 * 29 = x - 143

-37.178 = x - 143

x = - 37.178 + 143

x = 105.813