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Finding the Fourth Proportional to 390.21, 584.09 and 308.19

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Solution

The fourth proportional to 390.21, 584.09 and 308.19 is: 461.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.21 : 584.09 = 308.19 : x
  2. Step 2: Convert to fraction form
    390.21/584.09 = 308.19/x
  3. Step 3: Cross multiply
    390.21x = 584.09 × 308.19
  4. Step 4: Simplify right side
    390.21x = 180,010.70
  5. Step 5: Solve for x
    x = 180,010.70/390.21
  6. Step 6: Final answer
    x = 461.32

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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.