Last Year, Brand a Mobile Android Phones Had 45% of the Market

question 90

Essay

Last year, Brand A mobile android phones had 45% of the market, Brand B had 35% and Brand C had 20%. This year the makers of Brand C launched a heavy advertising campaign. A random sample of mobile phone stores shows that of the 10 000 android mobile phones sold, 4350 were Brand A, 3450 were Brand B, and 2200 were Brand
C. Has the market changed? Test at $\alpha =$ 0.05.

---

Definitions:

Agent of Necessity

A person who is appointed to act on behalf of another in situations of urgent necessity, without prior authorization from the principal.

Extravagance

The act or habit of spending more money than is necessary or wise; often associated with lavish or luxurious expenditure.

Credit Card

A plastic card issued by banks or financial institutions allowing the holder to borrow funds at the point of sale, which they then pay back at a later date.

Non-necessary Purchases

Expenditures on items or services that are not essential for basic living or business operations.