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Finding the Fourth Proportional to 419.31, 630.18 and 389.13

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Solution

The fourth proportional to 419.31, 630.18 and 389.13 is: 584.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.31 : 630.18 = 389.13 : x
  2. Step 2: Convert to fraction form
    419.31/630.18 = 389.13/x
  3. Step 3: Cross multiply
    419.31x = 630.18 × 389.13
  4. Step 4: Simplify right side
    419.31x = 245,221.94
  5. Step 5: Solve for x
    x = 245,221.94/419.31
  6. Step 6: Final answer
    x = 584.82

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.