使用逆运算
Using inverse operations
认识并利用运算之间的关系，包括逆运算；利用这些关系来检验答案和简化计算。
Recognise and use relationships between operations including inverse operations; use these relationships to check answers and simplify calculations
学习证据 / Evidence
- 使用加法和减法作为逆运算来检验和解决问题。
- 使用乘法和除法作为逆运算来检验和解决问题。
- 认识到平方和开平方互为逆运算。
- Use addition and subtraction as inverse operations to check and solve problems
- Use multiplication and division as inverse operations to check and solve problems
- Recognise that squaring and square-rooting are inverse operations
评估问题 / Assessment
如果{{name}}算出“252 ÷ 7 = 36”，他们能否马上利用逆运算来检验——“36 × 7 = 252”——而不必重新做除法？
If {{name}} works out '252 ÷ 7 = 36', can they immediately use the inverse to check — '36 × 7 = 252' — without having to redo the division?