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Each game has 10 questions.

Green box means correct.

Yellow box means incorrect.

Unlock harder levels by getting an average of 80% or higher.

Earn up to 5 stars for each level

The more questions you answer correctly, the more stars you'll unlock!

Each game has 10 questions.

Green box means correct.

Yellow box means incorrect.

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Grade 3 - Patterning and Algebra

Standard 3.PA.2 - Simplify both sides of the equation and find the missing number that makes the equation true.

Included Skills:

Expressions and Equality

• determine, through investigation, the inverse relationship between addition and subtraction (e.g., since 4 + 5 = 9, then 9 - 5 = 4; since 16 - 9 = 7, then 7 + 9 = 16);

• determine, the missing number in equations involving addition and subtraction of one- and two-digit numbers, using a variety of tools and strategies (e.g., modelling with concrete materials, using guess and check with and without the aid of a calculator) (Sample problem: What is the missing number in the equation 25 - 4 = 15 + ?);

• identify, through investigation, the properties of zero and one in multiplication (i.e., any number multiplied by zero equals zero; any number multiplied by 1 equals the original number) (Sample problem: Use tiles to create arrays that represent 3 x 3, 3 x 2, 3 x 1, and 3 x 0. Explain what you think will happen when you multiply any number by 1, and when you multiply any number by 0.);

• identify, through investigation, and use the associative property of addition to facilitate computation with whole numbers (e.g., "I know that 17 + 16 equals 17 + 3 + 13. This is easier to add in my head because I get 20 + 13 = 33.").

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