A denominate number is a number used with a unit of measurement in order to show the length, weight, capacity, temperature, etc... of something.
For example, the length of car is a denominate number because you have to associate the number you find when you measure your car with a unit of measurement such as inches, meter, feet, or else.
Length of a car could be equal to 16 feet.
The number 16 without a unit next to it is just a number.
2 cups
8 fluid ounces
2000 meters
1 liter
20 kilograms
60 years
180 seconds
9 volts
15 miles
100 m2
1850