Since there are 60 minutes in a hour we have:
- 60/15=4, so 15 minutes is 1/4 of a hour
- 60/10=6, so 10 minutes is 1/6 of a hour
- 60/3=20, so 3 minutes is 1/20 of a hour
Since there are 3 feet in a yard, 1 foot is 1/3 of a yard
Since a dozen means 12, and 12/6=2, 6 eggs is 1/2 of a dozen
Since a quarter is 25 cents, and 25/5=5, 5 cents is 1/5 of a quarter.