Question

The recommended daily dietary allowance for zinc among males older than age 50 years is 15 mg/day. An article reports the following summary data on intake for a sample of males age 65−74 years: n = 117, x = 12.8, and s = 6.45. Does this data indicate that average daily zinc intake in the population of all males age 65−74 falls below the recommended allowance? (Use α = 0.05.)
Calculate the test statistic and determine the P-value. (Round your test statistic to two decimal places and your P-value to four decimal places.)

z =

p-value =

Answer 1

Solution:

Test statistic = z

= ( - ) / s / n

= (12.8 - 15) / 6.45 / 117

Test statistic = -3.69

P-value = 0.0002