Units give numbers meaning. Units are vitally important to make sense of results in science. In this class, NO credit will be given for answers without units, and reduced credit will be given for answers with incorrect units. Therefore, it will be in your best interest to be aware of and utilize units to their fullest.
Units can also be helpful in determining how to get an answer.
This is indeed the case. We know there are 12 inches in a foot. 36 inches Notice how the foot units cancel to leave us with what we need, inches. All units are standardized across the world. The meter is based on the wavelength of a certain color of light.