A consumer product magazine recently ran a story concerning the increasing prices of digital cameras. The story stated that digital camera prices dipped a couple of years ago, but are now beginning to increase in price because of added features. According to the story, the average price of all digital cameras a couple of years ago was $215.00. A random sample of cameras was recently taken and entered into a spreadsheet. It was desired to test to determine if that average price of all digital cameras is now more than $215.00. What null and alternative hypothesis should be tested? A) $\mathrm { H } _ { 0 } : \mu = 215$ vs. $\mathrm { H } _ { \mathrm { A } } : \mu

Question

A consumer product magazine recently ran a story concerning the increasing prices of digital cameras. The story stated that digital camera prices dipped a couple of years ago, but are now beginning to increase in price because of added features. According to the story, the average price of all digital cameras a couple of years ago was $215.00. A random sample of cameras was recently taken and entered into a spreadsheet. It was desired to test to determine if that average price of all digital cameras is now more than $215.00. What null and alternative hypothesis should be tested? 
A) $\mathrm { H } _ { 0 } : \mu = 215$ vs. $\mathrm { H } _ { \mathrm { A } } : \mu < 215$
B) $\mathrm { H } _ { 0 } : \mu \geq 215$ vs. $\mathrm { H } _ { \mathrm { A } } : \mu < 215$
C) $\mathrm { H } _ { 0 } : \mu = 215$ vs. $\mathrm { H } _ { \mathrm { A } } : \mu \neq 215$
D) $\mathrm { H } _ { 0 } : \mu = 215$ vs. $\mathrm { H } _ { \mathrm { A } } : \mu > 215$

Quizplus · Accepted Answer

The null hypothesis ($\mathrm { H } _ { 0 }$) assumes no change, so $\mu = 215$. The alternative hypothesis ($\mathrm { H } _ { A }$) tests if the average price is now more than $215, so $\mu > 215$.

A Consumer Product Magazine Recently Ran a Story Concerning the Increasing