Using absolute value, it is found that:
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[tex]|D - 6.5| \leq 0.04[/tex]
Thus:
[tex]-0.04 \leq D - 6.5 \leq 0.04[/tex]
The solutions are:
[tex]D - 6.5 \geq -0.04 \rightarrow D \geq 6.46[/tex]
[tex]D - 6.5 \leq 0.04 \rightarrow D \leq 6.54[/tex]
Which means that:
A similar problem is given at https://brainly.com/question/24712564