determine the smallest 3-digit number which is exactly divisible by 6, 8 and 12.
Determine the smallest 3-digit number which is exactly divisible by 6, 8, and 12.
Answer: To find the smallest 3-digit number which is exactly divisible by 6, 8, and 12, follow these steps:
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Find the Least Common Multiple (LCM) of 6, 8, and 12:
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First, find the prime factorizations of 6, 8, and 12.
6 = 2^1 \times 3^18 = 2^312 = 2^2 \times 3^1 -
Then, determine the LCM by taking the highest power of each prime that appears in the factorizations.
\text{LCM} = 2^3 \times 3^1 -
Calculate the LCM:
2^3 = 83^1 = 3\text{LCM} = 8 \times 3 = 24
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Identify the smallest 3-digit number:
- The smallest 3-digit number is 100.
- We need to find the smallest 3-digit number that is a multiple of 24.
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Divide 100 by 24 and round up to the next integer:
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Calculate \frac{100}{24}:
\frac{100}{24} \approx 4.1667 -
Round up to the next integer to get the smallest integer k:
k = \lceil 4.1667 \rceil = 5
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Multiply the LCM by this smallest integer k:
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Calculate 24 \times 5:
24 \times 5 = 120
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Therefore, the smallest 3-digit number which is exactly divisible by 6, 8, and 12 is \boxed{120}.