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Finding the Fourth Proportional to 509.13, 702.39 and 312.30

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Solution

The fourth proportional to 509.13, 702.39 and 312.30 is: 430.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.13 : 702.39 = 312.30 : x
  2. Step 2: Convert to fraction form
    509.13/702.39 = 312.30/x
  3. Step 3: Cross multiply
    509.13x = 702.39 × 312.30
  4. Step 4: Simplify right side
    509.13x = 219,354.93
  5. Step 5: Solve for x
    x = 219,354.93/509.13
  6. Step 6: Final answer
    x = 430.85

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.