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Question
Two workers on the same job show the following results:
|
Worker P |
Worker Q | |
| Mean time for completing the job (hours) | 33 | 21 |
| Standard Deviation (hours) | 9 | 7 |
Regarding the time required to complete the job, which worker is more consistent?
Solution
| Worker P | Worker Q | |
| Mean time for completing the job (hours) | `bar"p"` = 33 | `bar"q"` = 21 |
| Standard Deviation (hours) | `sigma_"P"` = 9 | `sigma_"Q"` = 7 |
C.V. (P) = `(sigma_"p")/(bar"p") xx 100`
= `(9)/(33) xx 100`
= 27.27%
C.V. (Q) = `(sigma_"q")/(bar"q") xx 100`
= `7/21xx100`
= 33.33%
Since, C.V. (P) < C.V. (Q)
∴ Worker P is more consistent regarding the time required to complete the job.
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