Sixteen ounces in a pound — not ten, not a hundred. That is what makes customary weight the harder half of the standard: the factor is one a child has to know and actually multiply by. These free printable sheets convert ounces and pounds.
Metric weight leans on powers of ten; customary weight has sixteen to lean on instead, so every conversion is a real multiplication or division. 2 lb is 32 oz because 2 × 16 is 32; 48 oz is 3 lb because 48 ÷ 16 is 3. The numbers stay whole or half so the sixteen is the work, not the arithmetic around it.
Why this sheet works
Both directions appear on every page, and each question is a single rung — ounces to pounds, or pounds to ounces. Knowing the one fact cold, sixteen ounces to the pound, is what the sheet drills, the same way the metric sheets drill the powers of ten.
How this one works
One question from this sheet, worked through a step at a time.
5 lb = ? oz
lb → ozsmaller unit, bigger number
1 lb =16 oz
5 × 16 =80
80 oz
One oz is smaller than one lb, and it takes MORE of a small thing to make the same amount. So the number has to get bigger — which means multiplying.
There are 16 oz in one lb, so that is the number to multiply by.
5 × 16 = 80, so 5 lb is 80 oz. Check the direction held: the number got bigger, which is what a smaller unit does.
