All solutions here are SUGGESTED. Mr. Teng will hold no liability for any errors. Comments are entirely personal opinions.
For to be not rejected at 5% level of significance, then
From the graphing calculator, p-value , we reject .
Thus, there is sufficient evidence at 5% level of significant to conclude that the mean salt content has been reduced.
Read carefully that it is two-tailed and perform the test. Bare in mind to leave answers in set notation.
[…] 2013 A-level H1 Mathematics (8864) Question 10 Suggested Solutions […]