One thing as a Percentage of another
What percentage of an hour is 30mins? = 30/60 *100 = 50%
What percentage of an hour is 15mins? = 30/60 *100 = 25%
What percentage of an hour is 45mins? = 30/60 *100 = 75%
What percentage of an hour is 20mins? = 20/60 *100 = 33.3%
What percentage of an hour is 12mins? = 12/60 *100 = 20%
What percentage of an hour is 5mins? = 5/60 *100 = 8.3%