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The LCM of two numbers which are in the ...

The LCM of two numbers which are in the ratio 3:8 is 144 . Find the two numbers

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To find the two numbers that are in the ratio of 3:8 and have an LCM of 144, we can follow these steps: ### Step 1: Represent the numbers in terms of a variable Let the two numbers be represented as: - First number = 3x - Second number = 8x ### Step 2: Use the formula for LCM The LCM of two numbers can be calculated using the formula: \[ \text{LCM}(a, b) = \frac{a \times b}{\text{GCD}(a, b)} \] However, since we are dealing with numbers in a ratio, we can directly calculate the LCM as: \[ \text{LCM}(3x, 8x) = \frac{3x \times 8x}{\text{GCD}(3x, 8x)} \] ### Step 3: Find GCD of the numbers The GCD of 3x and 8x is: \[ \text{GCD}(3x, 8x) = x \] This is because 3 and 8 have no common factors other than 1. ### Step 4: Substitute GCD into the LCM formula Now substituting the GCD into the LCM formula: \[ \text{LCM}(3x, 8x) = \frac{3x \times 8x}{x} \] This simplifies to: \[ \text{LCM}(3x, 8x) = 3 \times 8 \times x = 24x \] ### Step 5: Set the LCM equal to the given value We know from the problem that the LCM is 144: \[ 24x = 144 \] ### Step 6: Solve for x To find x, divide both sides by 24: \[ x = \frac{144}{24} = 6 \] ### Step 7: Find the two numbers Now we can find the two numbers: - First number = 3x = 3 × 6 = 18 - Second number = 8x = 8 × 6 = 48 ### Final Answer The two numbers are 18 and 48. ---
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