Recommended first: Perimeter and area. You can still continue here.
A foot is bigger than an inch, so one foot holds 12 inches. Moving to a smaller unit always gives a bigger number. That single idea tells you whether to multiply or divide.
| Length | Time | Weight |
|---|---|---|
| 1 ft = 12 in | 1 min = 60 s | 1 lb = 16 oz |
| 1 yd = 3 ft | 1 hr = 60 min | 1 kg = 1000 g |
| 1 m = 100 cm | 1 day = 24 hr | 1 ton = 2000 lb |
Work through it
How many inches are in 5 feet?
Inches are smaller, so expect more. Multiply.
Calculate. inches
How many hours is 180 minutes?
Hours are bigger, so expect fewer. Divide.
Calculate. hours
Watch out for this
Dividing when going to a smaller unit.
Ask if the answer should get bigger or smaller before you calculate.
The short version
Smaller unit: multiply, because you need more of them. Bigger unit: divide.
Smaller unit: multiply, because you need more of them. Bigger unit: divide.
Your turn
Prefer paper? Print the Measurement and data worksheet, with an answer key.
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