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The manufacturer of an MP3 player wanted to know whether a 10% reduction in pric

ID: 2842346 • Letter: T

Question

The manufacturer of an MP3 player wanted to know whether a 10% reduction in price is enough to increase the sales of its product. To investigate, the owner randomly selected eight outlets and sold the MP3 player at the reduced price. At seven randomly selected outlets, the MP3 player was sold at the regular price. Reported below is the number of units sold last month at the sampled outlets.

     
   

  Regular price

127  

137  

107  

111  

89  

76  

71  

  

  Reduced price

  89  

130  

107  

106  

82  

127  

119  

122  

  
   

  
   

At the .010 significance level, can the manufacturer conclude that the price reduction resulted in an increase in sales? Hint: For the calculations, assume the Reduced price as the first sample.

  
   

  
   

  

  Regular price

127  

137  

107  

111  

89  

76  

71  

  

  Reduced price

  89  

130  

107  

106  

82  

127  

119  

122  

Explanation / Answer


The pooled variance is

s1^2/n1+s2^2/n2= 25.03^2/7+ 17.58^2/8 =128.1322


The test statistic is

t=(xbar1-xbar2)/128.1322

=(102.57-110.25)/128.1322

=-0.0599

Regular price Reduced price
102.57 110.25 mean 25.03 17.58 std. dev. 7 8 n