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Finding the Fourth Proportional to 285.38, 393.82 and 154.39

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Solution

The fourth proportional to 285.38, 393.82 and 154.39 is: 213.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.38 : 393.82 = 154.39 : x
  2. Step 2: Convert to fraction form
    285.38/393.82 = 154.39/x
  3. Step 3: Cross multiply
    285.38x = 393.82 × 154.39
  4. Step 4: Simplify right side
    285.38x = 60,800.78
  5. Step 5: Solve for x
    x = 60,800.78/285.38
  6. Step 6: Final answer
    x = 213.05

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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.