Problem 47 · The Museum DisplayPrint one blank worksheet now, download its PDF, or prepare a family or classroom packet.
MathJewels.com
Name
Date

The Museum Display

Complete to collectGarnet CrystalLevel 3 · 5 Glints

The museum has 6 display cases. Each case begins with 4 rubies. The curator may choose some of the cases to receive 3 sapphires each. Just before opening, the curator removes 5 jewels to polish them. She wants to share the remaining jewels equally among 5 display trays.

Cases with sapphiresJewels left after polishingShares equally into 5 trays?
0
1
2
3
4
5
6

Which choices for the number of sapphire cases let the curator share the remaining jewels equally among 5 trays? Find every choice from 0 through 6. For each choice that works, tell how many jewels go on each tray.

Complete the case table here. Use scratch paper for equations, checks, and your explanation that no other choice works.

At a glance

About this problem

These tags show what the problem is about and the math you’ll use. Choose one to find similar problems.

Skills

Helpful first

Grade

Math area

Topics

Is this a good fit?

Before you choose this problem

A plain-language look at readiness, thinking, time, and the expected response.

Math readiness

Designed for Grade 3

Uses Middle Grade 3 math.

Thinking

Stretch challenge

A nontrivial plan using familiar mathematical ideas.

Time & response

About 5–12 minutes

Moderate amount of written work · Short Explanation response.

How to support: Invite the learner to test a small set of case choices and ask how they know the list is complete.

Keep exploring

Keep exploring

Technical reference

Rating, skills & curriculum

Designed for Grade 3 · Uses Middle Grade 3 math · About 5–12 minutes

Grade 3 · Operations and computation · Multiplication and division · Addition and subtraction

MJ 3.4 · C3 · W2

Precise MJD coordinates, factor scores, skill weights, calibration evidence, and curriculum crosswalks. This reference is available to everyone and is intentionally last.

Content level

MJ 3.4

Grades 3–5

Grade 3 progression · point 4

Likely range
MJ 3.3–3.5
Confidence
90%

Challenge

C3 · Stretch

A nontrivial plan using familiar mathematical ideas.

  • Method selection2
  • Reasoning depth2
  • Novelty1
  • Constraint management2
  • Proof or justification2

Workload

W2 · Moderate

Several coordinated calculations, representations, or explanation steps.

Active time
5–12 minutes · typically 8
Response
Short Explanation
Known-method steps
10
  • Mechanical execution2
  • Written output2
  • Representation production1
  • Bookkeeping2

Learning focus

Skills this problem practices

What a successful response demonstrates, with each skill’s share of the content rating.

  • Interpret a product as equal groups or a rectangular array

    The learner can interpret a product as equal groups or a rectangular array. This capability is distinct from mere exposure to or isolated use of Grade 2 arrays.

    • Independent mastery
    • 36% focus
    • MJ 3.2 milestone
  • Interpret whole-number quotients as sharing or grouping

    The learner can interpret whole-number quotients as sharing or grouping. This capability is distinct from mere exposure to or isolated use of equal groups.

    • Independent mastery
    • 36% focus
    • MJ 3.4 milestone
  • Solve one- and two-step addition/subtraction stories within 100

    The learner can solve one- and two-step addition/subtraction stories within 100. This capability is distinct from mere exposure to or isolated use of Grade 1 story structures.

    • Independent mastery
    • 29% focus
    • MJ 2.3 milestone

Readiness

Helpful prerequisites

Skills the rating assumes are already available to the learner.

  • Interpret a product as equal groups or a rectangular array

    The learner can interpret a product as equal groups or a rectangular array. This capability is distinct from mere exposure to or isolated use of Grade 2 arrays.

    • Independent readiness
    • Required
    • MJ 3.2 milestone
  • Solve one- and two-step addition/subtraction stories within 100

    The learner can solve one- and two-step addition/subtraction stories within 100. This capability is distinct from mere exposure to or isolated use of Grade 1 story structures.

    • Fluent readiness
    • Required
    • MJ 2.5 milestone

External alignment

Curriculum and standards crosswalks

Approved evidence-backed locations that support discovery. They do not define the MathJewels rating.

Bridges in Mathematicsthird-edition · 23 locations
Modules14 locations · Representative: Module 4: Adding & Subtracting to 20
Number Corner workouts9 locations · Representative: September: Calendar Grid
Common Core State Standards for Mathematics2010 · 3 locations
Standards3 locations · Representative: Use addition and subtraction within 100 to solve one- and two-step word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem.