Measuring the distance from [tex]I_1 \ to \ I_1'[/tex] and dividing by 2 has advantage of achieving a more accurate result compared to measurement taking directly.
Measuring the distance from [tex]I_1 \ to \ I_1'[/tex] is equivalent to the double of the distance.
This method of measurement gives a more accurate result because it minimizes error that may result from taking readings form the intervals. It ensures more accurate result compared to the measurement obtained when [tex]OI_1[/tex] is measured directly.
[tex]OI_1 = \frac{I_1 + I_1'}{2}[/tex]
Thus, we can conclude that measuring the distance from [tex]I_1 \ to \ I_1'[/tex] and dividing by 2 has advantage of achieving a more accurate result compared to measurement taking directly.
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