SCENARIO 8-12-A
You Are the Quality Control Manager of a Water

question 179

Short Answer

SCENARIO 8-12-A
You are the quality control manager of a water bottles company. One of the biggest complaints in the
past years has been the breakage and, hence, the concern on the durability of the connector between
the lid and the bottle which many users use as a handle for the bottles. To collect evidence before
implementing any modification to the production process, your department has subjected 50 water
bottles to a durability test and the following data on the number of times the handles have been used
to lift the bottles before they break are contained in the file SCENARIO 8-12-A.XLSX. $$\begin{array} { l l l l l l l l l l } 495 & 499 & 502 & 500 & 491 & 498 & 498 & 495 & 488 & 516 \\513 & 486 & 504 & 503 & 493 & 504 & 489 & 500 & 495 & 499 \\501 & 507 & 511 & 496 & 486 & 497 & 510 & 504 & 493 & 482 \\511 & 502 & 520 & 514 & 486 & 514 & 500 & 505 & 512 & 500 \\504 & 498 & 503 & 514 & 474 & 489 & 488 & 506 & 517 & 490\end{array}$$ Assume that and the number of times the handles have been used to lift the bottles before they break
follows a normal distribution.
-Referring to Scenario 8-12-A, the width of the 95% confidence interval for the mean number of
times the handles have been used to lift the bottles before they break is _____.

---

Definitions:

Coupon

The interest rate on a bond that the issuer promises to pay to the holder until maturity, usually expressed as an annual percentage.

Tax Rate

The proportion of income, profits, or other bases that is paid or levied as tax by the government, typically expressed as a percentage.

Cost of Preferred Stock

The effective rate that a company pays on its issued preferred shares, calculated by dividing the dividend by the current price of the stock.

Par Value

The face value of a bond or stock, as stated by the issuing company, which does not necessarily reflect market value.