C HOOSING THE A PPROPRIATE C USTOMARY U NITS Choose the most appropriate customary unit for each measurement. Justify your answer. A. The length of a rug Feet-you can use sheets of paper to measure the length B. The weight of a magazine Ounces-the weight of a magazine is about the weight of several slices of bread C. The capacity of an aquarium Gallons-you can fill an aquarium with gallon jugs of water.
C OMMON E QUIVALENT C USTOMARY U NITS LengthCapacity 12 inches (in)= 1 foot (ft)8 fluid ounces (fl oz) = 1 cup (c) 3 feet = 1 yard (yd)2 c = 1 pint (pt) 5,280 ft = 1 mile (mi)2 pt = 1 quart (qt) 1,760 yds= 1 mi4 qt = 1 gallon (gal) Weight 16 ounces (oz) = 1 pound (lb) 2,000 lbs = 1 ton
T RY T HIS !!! Method 1: Proportions Write a proportion Method 2: Multiply by 1 Multiply by a ratio equal to 1 and divide out the units Convert 19 c to fl oz 19 cups is equal to 152 fluid ounces
T RY T HIS !!! A carpenter has a wooden post that is 4 ft long. She cuts off 17 in the end of the post. What is the remaining length? The carpenter cuts off 17 in. Write answer in both feet and inches First convert 4 ft to in Use 1 ft = 12 in Multiply by ratio equal to 1
E XAMPLE 1: Choose the most appropriate customary unit for each measurement. Justify your answer. A. The weight of a car B. The diameter of a soup can C. The weight of a newborn baby