The lightest bird in the world is the hummingbird. A sparrow weighs 1 gram more than 80 times that of a hummingbird. A sparrow weighs 81 grams, how many grams is a hummingbird? (solution by equation)
世界上最轻的鸟是蜂鸟，一只麻雀的重量比一只蜂鸟的80倍还多1克．一只麻雀重81克，一只蜂鸟多少克？(用方程解)
<gadget id="calculator">81 - 1</gadget>
<output>80</output>

<gadget id="calculator">80 / 80</gadget>
<output>1</output>

<result>1</result>