Changing Units in the Customary System

1. Changing Units in the Customary System Lesson 5-8

3. Strategy • When converting from a large unit to a small unit, multiply by the conversion factor. • When converting from a small unit to a larger unit, divide by the conversion factor.

4. Small - - - - - - - - Large Inch (in) ---------- Foot (ft)-------- Yard (yd) ------- Mile (mi) Ounce (oz) -------------- Pound (lb) -------------Ton (t) Fluid Ounce (fl. oz.) -- Cup (c) -- Pint (pt) -- Quart (qt) -- Gallon (gal)

5. Changing Units • Determine the direction of the change (LS or SL) • Multiply or Divide by the appropriate conversion unit.

6. Example 48 12 gal = ______ qt L  S 12 x 4 (1 gal = 4 qt)

7. Example 2 40 in = ______ ft S  L 40 ÷ 12 1 1 We can divide fractions so that remainders can be described as fractions. 10 40 x 1 1 12 3 10 3 1 = 3 3

8. Computing With Units • Combine or subtract like units. • Regroup. 19 7 1 foot = 12 inches 8 feet 7 inches - 5 feet 11 inches 2 feet 8 inches

9. Homework Time