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CRACK THE CODE · GRADE 2

Prehistoric Hoops Math Quest

Solve the symbol equations to figure out the four-digit combination for the dinosaur basketball team's equipment locker.

Each shape stands for a number. Then solve the shape equations and read off the 4-digit code. Do it here or print the sheet — the answer key comes with it.

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The key

=9
=2
=1
=8
=10

Every symbol is a whole number from 1 to 10. A number in front of a shape means multiply: 2 stars = 2 x star.

Crack these

  1. 1.+2=
  2. 2.+=CODE 1
  3. 3.+2=
  4. 4.2+2=CODE 2
  5. 5.++=
  6. 6.+=CODE 3
  7. 7.2=
  8. 8.2+=CODE 4
  9. 9.?+=9Which shape?
  10. 10.+?=18Which shape?

The vault code

Take the ones digit of your answers to problems 2, 4, 6, 8 (the ones tagged CODE 1–4), in that order. That opens the dinosaur basketball equipment.

Show answer key (for grown-ups)

Key: cross = 9 · star = 2 · heart = 1 · pentagon = 8 · square = 10

Every symbol is a whole number from 1 to 10.

1.star + 2 x heart4
2.cross + square19
3.square + 2 x heart12
4.2 x cross + 2 x star22
5.star + cross + heart12
6.star + square12
7.2 x heart2
8.2 x square + cross29
9.? + pentagon = 9heart
10.pentagon + ? = 18square

Vault code: 9229

About Crack the Code

Crack the Code is early algebra without the letters: a key maps shapes to numbers, and the kid substitutes, computes, and — from grade 3 up — deduces hidden values from shape equations before they can solve anything. Grade 2 practices addition, subtraction, and multiplying by 2 and 3. Every sheet has exactly one right key and one right code.

It's one of three things Math Crackers makes, free and printable, personalized to what your kid is into: a full math whodunit, a Lab Work sheet of multi-step word problems, or a Crack the Code sheet like this one. Browse free printable worksheets by grade, skill, and theme.

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