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Probability

Rule of Sum and Rule of Product

Concept Quizzes

Rule of Sum and Rule of Product Warmup
Rule of Sum
Counting Integers in a Range
Rule of Sum Problem Solving
Rule of Product
Rule of Product Problem Solving
Rule of Sum and Rule of Product Problem Solving
Map Coloring

Challenge Quizzes

Rule of Sum and Rule of Product: Level 1 Challenges
Rule of Sum and Rule of Product: Level 2 Challenges
Rule of Sum and Rule of Product: Level 3 Challenges

Rule of Sum and Rule of Product: Level 2 Challenges

5 12 6 10 11

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by Zandra Vinegar

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When we write the integers from 1 to 100, how many times does the digit 9 appear?

11 20 10 19

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by Dinesh Nath Goswami

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Which of the following expresses the correct formula for the number of unit squares with exactly 1 red side in an $n \times n$ square with $n \geq 2$ ?

(n-2)^2

4(n-2)

n^2 - 8

4n - 4

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by Arron Kau

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Find the number of $2$ digit numbers whose digit sum is a perfect square.

17

16

14

13

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by Krishna Ar

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If you take a $3 \times 3 \times 3$ Rubik cube and break it up into the $3^3$ cubes, how many cubes would have stickers on exactly $2$ faces?

Bonus question: Can you generalize this for a $N \times N \times N$ Rubik cube?

9 26 3 27 8 12 6

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by Chung Kevin

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