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 regular and reduced prices at the randomly selected outlets.

Regular price	137	126	89	112	118	125	94
Reduced price	126	131	150	137	112	127	131	133

At the 0.100 significance level, can the manufacturer conclude that the price reduction resulted in an increase in sales? Hint: For the calculations, assume reduced price as the first sample.

Answer 1

Given
X1 bar	130.875(AVERAGE())	X2 bar	114.4286
S1	10.70964185(STDEV())	S2	17.50102
n1	8	n2	7

Hypothesis :		α=	0.1
		df	13	n1+n2-2
Ho:	μ1​ = μ2
Ha:	μ1​ > μ2
t Critical Value :
tc	1.350171289	T.INV(1-D1,9)	RIGHT
ts	>=	tc	RIGHT	To reject
Test :
Sp^2	203.1222527	((n1-1)S1^2+(n2-1)S2^2)/(n1+n2-2)
t	2.229673308	(X1 bar-X2 bar )/SQRT(Sp^2*(1/n1 + 1/n2))	Equal vriance
P value :
P value	0.025117287	T.DIST.RT(ts,df)	RIGHT
Decision :
P value	<	α	Reject H0

There is enough evidence to claim that the price reduction resulted in an increase in sales, at the 0.100 significance leve