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A rational number is any number that can be expressed as the quotient of two integers, where the denominator is not zero. For example, 1/2, 3, and -4.75 are rational numbers. |
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A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself. A composite number is a natural number greater than 1 that has more than two positive divisors. For example, 2 is prime, while 4 is composite. |
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A number is divisible by 3 if the sum of its digits is divisible by 3. For example, for the number 123, the sum of the digits is 1 + 2 + 3 = 6, which is divisible by 3, so 123 is also divisible by 3. |
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Let the integers be n and n + 1. Then n(n + 1) = 240. This simplifies to n² + n - 240 = 0. Factoring gives (n - 15)(n + 16) = 0. Therefore, n = 15 (the positive solution), so the integers are 15 and 16. |
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To find the LCM, first determine the prime factorization of each number: 12 = 2² * 3 and 15 = 3 * 5. The LCM is found by taking the highest power of each prime: LCM = 2² * 3¹ * 5¹ = 60. |
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To find the GCD, we can use prime factorization: 48 = 2⁴ * 3¹ and 180 = 2² * 3² * 5¹. The GCD is found by taking the lowest power of each prime: GCD = 2² * 3¹ = 12. |
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To convert 1/8 into decimal, divide 1 by 8. The decimal representation is 0.125. |
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The prime numbers between 1 and 50 are 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, and 47. There are a total of 15 prime numbers. |
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The sum of the first n natural numbers is given by the formula n(n + 1)/2. For n = 10, the sum is 10(10 + 1)/2 = 10 * 11/2 = 55. |
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An irrational number is a number that cannot be expressed as a fraction of two integers. Its decimal representation is non-repeating and non-terminating. Examples include √2 and π. |
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A number is divisible by 9 if the sum of its digits is divisible by 9. For example, the number 729 has digits that sum to 7 + 2 + 9 = 18, which is divisible by 9, so 729 is also divisible by 9. |