Larger to Smaller Unit: MULTIPLY

Example: 3 feet to inches → 3 × 12 = 36 inches

Smaller to Larger Unit: DIVIDE

Example: 48 inches to feet → 48 ÷ 12 = 4 feet

Mixed units express a measurement using

TWO or MORE different units

Examples: 5 feet 8 inches, 3 pounds 12 ounces, 2 gallons 3 quarts

Example: Convert 45 inches to feet and inches

Step 1: Add or subtract the larger units

Step 2: Add or subtract the smaller units

Step 3: Convert if necessary (if smaller unit ≥ conversion factor)

kilo (k): 1,000 units (thousand)

hecto (h): 100 units (hundred)

deka (da): 10 units (ten)

BASE UNIT: meter (m), gram (g), liter (L)

deci (d): 0.1 unit (tenth)

centi (c): 0.01 unit (hundredth)

milli (m): 0.001 unit (thousandth)

Moving RIGHT (larger to smaller):

MULTIPLY by 10, 100, or 1000

Move decimal point RIGHT

Moving LEFT (smaller to larger):

DIVIDE by 10, 100, or 1000

Move decimal point LEFT

Step 1: Find the conversion factor

Step 2: Multiply by the conversion factor

Step 3: Round to appropriate decimal places

Fahrenheit (°F): Used in the United States

• Water freezes at 32°F

• Water boils at 212°F

Celsius (°C): Used in most other countries (metric)

• Water freezes at 0°C

• Water boils at 100°C

°F = (°C × 9/5) + 32

or

°F = (°C × 1.8) + 32

°C = (°F − 32) × 5/9

Problem: Convert 25°C to Fahrenheit

Problem: Convert 68°F to Celsius

✓ Customary: Larger to smaller = multiply, smaller to larger = divide

✓ Metric: Based on powers of 10 (easier conversions!)

✓ King Henry Died By Drinking Chocolate Milk (kilo, hecto, deka, base, deci, centi, milli)

✓ Mixed units: Use division with remainders

✓ Customary↔Metric: Use approximate conversion factors

✓ Temperature: Remember water freezes at 32°F/0°C, boils at 212°F/100°C

✓ C to F: Multiply by 9/5 (or 1.8), then add 32

✓ F to C: Subtract 32 first, then multiply by 5/9

✓ Always check units in your final answer

✓ Use ≈ symbol for approximate conversions between systems

Customary Length:

"12 inches per foot, 3 feet per yard - 5280 feet per mile, learn this hard!"

Metric Prefixes:

"King Henry Died By Drinking Chocolate Milk" = kilo, hecto, deka, BASE, deci, centi, milli

Conversion Direction:

"Big to small, multiply all! Small to big, divide you dig!"

Customary Capacity:

"2 cups in a pint, 2 pints in a quart, 4 quarts in a gallon - now you're smart!"

Temperature Conversion:

"C to F: times 9/5, add 32 to survive! F to C: subtract 32 first, times 5/9 to reverse!"

Metric Powers of 10:

"Metric is metric-ulous - just move the decimal, it's miraculous!"

Inch to Centimeter:

"2.54 for every inch - this conversion is a cinch!"