Question

It is claimed by a researcher that the proportion of people who consume Lay's Potato Chips is less than the proportion of people who consume Cheetos. Test the claim using α =0.01. The sample data is presented below.

Lay's Potato Chips	Cheetos
X 1 =35 n 1 =80	X 2 =60 n 2 =90

Round all proportions to 2 place values

p ^ 1 =

p ^ 2 =

p ¯=

q ¯=

State the claim:

H 0 p 1=p 2

H 1 p 1  p 2 claim

Determine the direction of the tails: Left, Right, or Two:

Find the critical value:

Compute Test Point (round to 2 place values) :

Do we Reject or Do Not Reject?  

Summarize: There is enough evidence to  the claim.

Answer 1

Solution:

Given

n1= 80 sample size of Lays potato.

n1= 90 sample size of chips Cheetos.

X1 = 35

X2 = 60.

round to two decimal places  sample proportion of Lays potato.

sample proportion of chips Cheetos.

. Pooled proportion

To test

Ho: p1=p2. Vs. Ha:p1 < p2

The direction of the tail is left tailed

The test is left tailed test.

The Z critical value at is

from Z table

The Z critical value = 2.33

Test statistic

Z = - 3.0154522

Test statistic Z = - 3.02

Decision :

3.02 > 2.33

Reject Ho .

Conclusion : There is sufficient evidence to conclude that the proportion of Lays potato chips is less than the proportion of people who consume chips Cheetos.