Problem 5 · 2016 Math Kangaroo
Easy
Arithmetic & Operations
off-by-one
Johannes hands out flyers to the houses with the numbers 15 to 47. How many houses get a flyer?
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Answer: C — 33
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Hint 1 of 2
Counting from 15 to 47 includes both end houses.
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Hint 2 of 2
The count is the difference of the numbers plus one.
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Approach: count an inclusive range
- The houses are numbered 15, 16, ..., 47.
- Count = 47 − 15 + 1 = 33 houses get a flyer.
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