Mathematics
Number Representation & Place Value
Procedural
12–14 yrs
Estimating by rounding
用四舍五入估算
Description
Use approximation through rounding to estimate answers and calculate possible resulting errors expressed using inequality notation a < x ≤ b; understand upper and lower bounds of rounded values
Mastery Evidence
- Estimate the answer to a calculation by rounding all values appropriately
- Calculate upper and lower bounds of a rounded measurement
- Express error intervals using inequality notation
Assessment Prompt
If a length is measured as 7 cm to the nearest cm, can your child say the actual length could be anywhere from 6.5 cm to 7.5 cm — understanding that rounding creates a range of possible values?
Prerequisites 1
Decimal place value (age 11+)
误差区间要求理解按指定精度进行的四舍五入
Unlocks 0
No follow-up topics
