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Finding the Fourth Proportional to 318.87, 478.20 and 102.39

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Solution

The fourth proportional to 318.87, 478.20 and 102.39 is: 153.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    318.87 : 478.20 = 102.39 : x
  2. Step 2: Convert to fraction form
    318.87/478.20 = 102.39/x
  3. Step 3: Cross multiply
    318.87x = 478.20 × 102.39
  4. Step 4: Simplify right side
    318.87x = 48,962.90
  5. Step 5: Solve for x
    x = 48,962.90/318.87
  6. Step 6: Final answer
    x = 153.55

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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.