Engineers of SY Spring Trading company who are in charge of the production of springs used to make car seats are concerned about the variability of the springs. The
springs are designed to be 500 millimeter (mm) long. If the springs are too long, they
will loosen and fall out and if the springs are too short, they will not fit into the frames.
The springs that are too long and too short must be reworked at an additional cost. The
engineers have calculated that a standard deviation of more than 2 mm will result in an
acceptable number of springs that must be reworked. A random sample of 96 springs
are measured and it is found that the length of the spring has variance of 6.7276.
i)
Can we conclude that the number of springs requiring reworking is extremely
large?
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