Well, since we know 30 is the unit rate of determining the weight of someone, in order to find the approximate number of quarters of blood in the person's body, all we'll have to do is divide the amount of pounds the person is divided by 30 to figure out the approximate number of quarters of blood in the person's body.So we'll do 120 divided by 30, which is 4.So there are 4 quarters of blood in the 120 pound person.
