心算乘除法(9岁及以上)
Mental multiplication and division (age 9+)
利用已知事实(包括相关事实和位值调整)进行心算乘法和除法。
Multiply and divide numbers mentally drawing upon known facts, including related facts and place-value adjustments
学习证据 / Evidence
- 利用4 × 6 = 24,然后在末尾添零,心算40 × 60。
- 通过计算7 × 10 + 7 × 5来推导7 × 15。
- 利用36 ÷ 9 = 4心算360 ÷ 9。
- Calculate 40 × 60 mentally by using 4 × 6 = 24 then appending zeros
- Derive 7 × 15 by calculating 7 × 10 + 7 × 5
- Calculate 360 ÷ 9 mentally using 36 ÷ 9 = 4
评估问题 / Assessment
{{name}}能否利用已知事实的巧妙联系,在脑中算出像'24 × 5'或'360 ÷ 8'这样的题目,而不需要写下来?
Can {{name}} work out things like '24 × 5' or '360 ÷ 8' in their head — using clever connections to known facts rather than needing to write anything down?