Problem 1 · 2015 Math Kangaroo
Easy
Algebra & Patterns
evaluate-formulaorder-of-operations
Start with the number in the first cloud and follow the arrows. The arrows say, in order, −0, then +1, then ×5. Which number is hidden behind the question mark?
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Answer: E — 15
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Hint 1 of 2
Start with the number in the first cloud and do what each arrow says, one arrow at a time.
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Hint 2 of 2
Taking away 0 keeps the number the same; then add 1, then make 5 copies of it.
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Approach: follow the operation chain left to right
- Begin with 2. The first arrow says −0, so it stays 2.
- The next arrow says +1, giving 3.
- The last arrow says ×5, giving 3 × 5 = 15.
- The hidden number is 15.
Mark:
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