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Finding the Fourth Proportional to 508.20, 701.24 and 311.78

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Solution

The fourth proportional to 508.20, 701.24 and 311.78 is: 430.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    508.20 : 701.24 = 311.78 : x
  2. Step 2: Convert to fraction form
    508.20/701.24 = 311.78/x
  3. Step 3: Cross multiply
    508.20x = 701.24 × 311.78
  4. Step 4: Simplify right side
    508.20x = 218,632.61
  5. Step 5: Solve for x
    x = 218,632.61/508.20
  6. Step 6: Final answer
    x = 430.21

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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.