If the Standard Deviation of the Lifetimes of Vacuum Cleaners

question 87

Short Answer

If the standard deviation of the lifetimes of vacuum cleaners is estimated to be 300 hours, how large of a sample must be taken in order to be 97% confident that the margin of error will not exceed 40 hours?

---

Definitions:

Average Total Cost Curve

A graph that shows a firm's per-unit cost (both fixed and variable) at various levels of output.

Upward-sloping

Describes a curve on a graph that moves higher as it goes from left to right, often used to illustrate the relationship between price and supplied quantity in supply curves.

Short-run Supply Curve

A graphical representation showing the quantity of goods that producers are willing to supply at various prices over a short period, where at least one input is fixed.

Perfectly Competitive Market

A theoretical market structure characterized by an infinite number of small firms, homogeneous products, perfect information, and ease of entry and exit.