Question

"Trydint" bubble-gum company claims that 8 out of 10 people prefer their gum to "Eklypse". Test their claim at the 99 confidence level.

The null and alternative hypothesis in symbols would be:

• H0:p≤0.8H0:p≤0.8
  H1:p>0.8H1:p>0.8
• H0:μ≤0.8H0:μ≤0.8
  H1:μ>0.8H1:μ>0.8
• H0:μ=0.8H0:μ=0.8
  H1:μ≠0.8H1:μ≠0.8
• H0:p=0.8H0:p=0.8
  H1:p≠0.8H1:p≠0.8
• H0:μ≥0.8H0:μ≥0.8
  H1:μ<0.8H1:μ<0.8
• H0:p≥0.8H0:p≥0.8
  H1:p<0.8H1:p<0.8

The null hypothesis in words would be:

• The proportion of people in a sample that prefer Trydint gum is not 0.8
• The proportion of people in a sample that prefers Trydint gum is 0.8.
• The proportion of all people that prefer Trydint gum is greater than 0.8.
• The proportion of all people that prefer Trydint gum is 0.8
• The proportion of all people that prefer Trydint gum is less than 0.8.
• The average of people that prefer Trydint gum is not 0.8.
• The average of people that prefer Trydint gum is 0.8.

Based on a sample of 120 people, 79 said they prefer "Trydint" gum to "Eklypse".

The point estimate is:  (to 3 decimals)

The 99 % confidence interval is:  to  (to 3 decimals)

Based on this we:

• Reject the null hypothesis
• Fail to reject the null hypothesis

Answer 1