Chapter 5 · Calculator

Lesson 5.3 · Use a calculator to calculate

Hua's Classroom for Shanghai Maths — One Lesson One Exercise (English edition, pages 102–104).

Grade 3 Second Semester Pages 102–104 ECNU Press

Lesson Alignment

How this Shanghai Maths lesson connects to learning goals, Common Core, and Eureka Math.

Learning Objectives

Students will be able to:

  1. 01Calculate multi-step expressions on a calculator. (Question 1)
  2. 02Follow correct key order for ÷ then −. (Question 2)
  3. 03Notice patterns such as $n \times 101$. (Question 3)

Common Core Standards

CodeStandard (focus for this lesson)
3.OA.D.8Multi-step problems.
4.NBT.B.5Multiply / divide check.

Eureka Math Correspondence

Shanghai MathsFocusEureka Math
PracticeKey sequencesG4 fluency
Patterns×101G4

Core Concepts

Use a calculator for multi-step ×÷; spot patterns like ×101.

Multi-Step Calc

Work left to right unless brackets group a step.

Key Order

For $2160 \div 20 - 57$: enter 2160, ÷, 20, =, then −, 57, =.

Number Patterns

$n \times 101$ patterns — check with a calculator, then write more examples.

Key Terms & Definitions (Reference)

Quick glossary for this lesson.

TermDefinition
Multi-stepMore than one operation.
PatternA repeating number relationship.

Key Answers

Quick reference for this lesson’s exercise answers.

1–2. Key order / check

  • $58209+4293=62502$ (keys $5\,8\,2\,0\,9\,+\,4\,2\,9\,3\,=$).
  • Check: $69\times34+1=2347$ — the division is correct.

3. Column / step + calculator

$7079\times830=5\,875\,570$;\; $623\times741=461\,643$;\; $3802+19578=23\,380$.

4–5

  • $2160\div20-57=51$.
  • Total spend $2398+396+180=2974$ yuan; public rental total $82\,240$ units.

6. Pattern ×101

  • $86\times101=8686$, etc.; two-digit $ab\times101$ “repeats” the digits.
  • $860\times101=86860$;\; $453\times101=45753$, etc. (append / carry pattern).
  • Examples: $99\times101=9999$;\; $20\times101=2020$;\; $354\times101=35754$;\; $416\times101=42016$.

7. Fastest route

Speeds (km/min): Route 1 $\approx0.45667$; Route 2 $0.56875$; Route 3 $\approx0.50882$. Route 2 is fastest.