Mathematics
Addition & Subtraction
Procedural
8–9 yrs
Two-Step Equations
两步方程
Description
Solve two-step word problems using the four operations; represent problems using equations with a letter standing for the unknown quantity
Mastery Evidence
- Solve a two-step problem that combines addition/subtraction with multiplication/division
- Write an equation using a letter for the unknown (e.g. 3 × n + 5 = 26)
- Assess the reasonableness of the answer using estimation and mental computation
Assessment Prompt
Can your child write an equation like 'n + 25 = 60' to represent a word problem, and then solve it to find what n equals?
Prerequisites 3
Fluent adding and subtracting within 1000
熟练掌握1000以内的运算，有助于解决混合运算问题
Rounding to 10, 100, 1000
用四舍五入进行估算，有助于评估答案的合理性
Two-Step Word Problems
两步四则运算问题是一步/两步加减法问题的延伸
Unlocks 0
No follow-up topics
