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The manufacturer of an MP3 player wanted to know whether a 10 percent reduction

ID: 3134441 • Letter: T

Question

The manufacturer of an MP3 player wanted to know whether a 10 percent 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

137

124

88

115

146

129

96

  

  Reduced price

127

132

152

138

116

104

114

116


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

137

124

88

115

146

129

96

  

  Reduced price

127

132

152

138

116

104

114

116

Explanation / Answer

H0: Mean before reduction = Mean after reduction

Ha: mu1 < mu2

Mean difference = -5.71

Since sample size is small t test is used

df = 14-1 =13

Pooled variance = 89.908

std error for difference = 9.482

t =-0.6027

p = 0.2775

As p >0.1, null hypothesis is accepted

There is no significant increase in sales due to price reduction

  Group   Group One     Group Two   Mean 119.29 125.00 SD 21.15 15.49 SEM 7.99 5.48 N 7     8