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Too odd

Number Theory Level 1

Out of the first 100 positive integers, how many odd primes are there?

Details and assumptions

You may use the fact that there are 25 prime numbers from 1 to 100.

Excel in math and science

Master concepts by solving fun, challenging problems.

It's hard to learn from lectures and videos

Learn more effectively through short, conceptual quizzes.

Our wiki is made for math and science

Master advanced concepts through explanations,
examples, and problems from the community.

Used and loved by 4 million people

Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.

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View solutions

by Arron Kau

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