If a non-square number has 18 different rectangular arrays, it means it has 18 different pairs of factors.
The number of factors of a number can be calculated by finding the prime factorization of the number and adding 1 to each exponent, and then multiplying the results. For example, the factors of 18 can be found by expressing it as a product of prime numbers: 18 = 2^1 * 3^2. Adding 1 to each exponent gives (1+1) * (2+1) = 2 * 3 = 6. Therefore, 18 has 6 factors.
So if a non-square number has 18 different rectangular arrays, it has 18 pairs of factors, and the total number of factors can be calculated in a similar way. We need to find two numbers whose exponents multiply to 18, and then add 1 to each exponent and multiply the results.
The prime factorization of 18 is 2^1 * 3^2. To find pairs of exponents that multiply to 18, we can consider the following possibilities:
1 * 18 = (1+1) * (18+1) = 2 * 19 = 38 factors
2 * 9 = (2+1) * (9+1) = 3 * 10 = 30 factors
3 * 6 = (3+1) * (6+1) = 4 * 7 = 28 factors
So a non-square number with 18 different rectangular arrays can have either 38, 30, or 28 factors, depending on the specific combinations of exponents in its prime factorization.
if any nonsquare number has 18 different rectangular arrays, how many factors does it havw
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