"Published in Newark, California, USA"
How deep a cut should be milled off one side of a 2 ½ in. shaft to make a flat (a rectangular flat area) 1 ⅛ in. wide?
Solution:
To illustrate the problem, it is better to draw the figure as follows
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| Photo by Math Principles in Everyday Life |
Since the length of a shaft is not given in the problem and the height or depth of a cut is required to make a flat at one side, then we can consider only the base and label further to analyze more the problem as follows
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| Photo by Math Principles in Everyday Life |
The radius of a shaft is
The value of x which is one half of the length of a flat in a shaft is
By Pythagorean Theorem, the value of y is
Therefore, the depth of a cut should be milled off one side of a shaft to make a flat is
