Mnemonic devices are memory techniques to improve your ability to recall information. For

example, the names of the Great Lakes are: Superior, Michigan, Huron, Erie, Ontario. You

can remember the order from west to east using this device: Super Man Helps Every One.

Fifth grade students are expected to know the names of the Great Lakes and location from

west to east. In an experiment, two independent groups of students were randomly assigned

to either study a U.S. map for two minutes or have this mnemonic device explained to them

for two minutes. Two weeks later, on the end of unit exam, teachers recorded how many

names and locations of the Great Lakes were correct.

a) Perform the correct inference procedure to determine if the mnemonic device significantly

increases retention at the = .05 significance level?

U.S. map: n= 56 x=2.1 s=0.9 lakes

Mnemonic device: n= 48 x=3.6 s=1 lake

b) Construct the corresponding confidence interval to determine the actual difference in means of

the number of Great Lakes that will be remembered.