Arithmetic Puzzles

Concept Quizzes

Logical Arithmetic Warmup
Fill in the Blanks Warmup
Arithmetic Puzzles - Fill in the Blanks
Arithmetic Puzzles - Operator Search
Number Guessing
Decanting
Balances Warmup
Hanging Balances

Challenge Quizzes

Arithmetic Puzzles: Level 1 Challenges
Arithmetic Puzzles: Level 2 Challenges
Arithmetic Puzzles: Level 3 Challenges
Arithmetic Puzzles: Level 4 Challenges
Arithmetic Puzzles: Level 5 Challenges

Arithmetic Puzzles - Operator Search

What series of signs will make the following equation true: $2 \, \square \, 2 \, \square \, 2 \, \square \, 2 = -6$

\div - \times

- \times -

- - \times

- \times \times

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by Brilliant Staff

Which of the following series of signs will make the following equation true: $2 \, \square \, 2 \, \square \, 2 \, \square \, 2 = 4?$

(a)~+ + -

(b)~+ \div +

(c)~\times + +

(d)~+ \div -

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by Brilliant Staff

What series of signs will NOT make the following equation true: $8 \, \square \, 8 \, \square \, 8 \, \square \, 8 = 0?$

\div - \div

- \div \times

\times \div -

\times - \div

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by Brilliant Staff

How many different 3-tuples $(\square,\triangle,\star)$ of operators make the following equation true: $6 \, \square \, (3 \, \triangle \, 2)=1 \, \star \, 1?$

Details and Assumptions

$\square,\triangle,\star$ can be one of the four arithmetic operators: $+,-,\times,\div.$
One kind of operator can be used more than once.

2 5 6 9 16

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by Brilliant Staff

What series of signs will NOT make the following equation true: $4 \, \square \, 4 \, \square \, 4 \, \square \, 4 = 16?$

\times + -

\div \times \times

\times \div +

+ \times -

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by Brilliant Staff