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Finding the Fourth Proportional to 318.85, 478.09 and 102.49

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Solution

The fourth proportional to 318.85, 478.09 and 102.49 is: 153.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    318.85 : 478.09 = 102.49 : x
  2. Step 2: Convert to fraction form
    318.85/478.09 = 102.49/x
  3. Step 3: Cross multiply
    318.85x = 478.09 × 102.49
  4. Step 4: Simplify right side
    318.85x = 48,999.44
  5. Step 5: Solve for x
    x = 48,999.44/318.85
  6. Step 6: Final answer
    x = 153.68

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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.