Question

An important part of any dispensing process is statistical quality control. At the Billy Goat Gruff Inn, machines are set to dispense 600 ml of soda into every customer's glass. Over time, however, the machine can get “out of control” and dispense too much soda or too little. The machine needs adjustment if the mean amount dispensed is different than 600 ml. At a random point in time each clock hour, the owner dispenses and checks a glass of dispensed soda and determines the actual volume of soda dispensed. One day the volumes of the dispensed soda were: 600.15, 599.92, 599.85, 599.92, 599.81, 600.14, 600.04, 599.98 The owner wants to see if there is a sufficient evidence to conclude that the dispensing machine needs some adjustment. Assuming that the population distribution is approximately normal, find the test statistics t. For calculation purpose, round x with bar on top and s to three decimal places; round the final answer for t to one decimal place. 0 -1.5 -0.4 -0.5

Answer 1

Null Hypothesis, 600

Alternative Hypothesis, 600

xbar = 599.951
s = 0.113
n = 8

Test statistic,

t = (599.951 - 600)/(0.113/sqrt(8))
t = -1.23 i.e. -1.2

t = -1.2