Answer:
1/5 of of an hour = 12 minutes
if 12 mins uses 1/6th then we use promotion
12 mins = 1/6
in other words
12/1 = 1/6
to get the entire package we invert the equation
therefore
12/1=6/1
12×6=72 mins
72 mins in hours =
1 hour 12 mins to use the entire package
