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Finding the Fourth Proportional to 381.18, 571.80 and 137.70

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Solution

The fourth proportional to 381.18, 571.80 and 137.70 is: 206.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    381.18 : 571.80 = 137.70 : x
  2. Step 2: Convert to fraction form
    381.18/571.80 = 137.70/x
  3. Step 3: Cross multiply
    381.18x = 571.80 × 137.70
  4. Step 4: Simplify right side
    381.18x = 78,736.86
  5. Step 5: Solve for x
    x = 78,736.86/381.18
  6. Step 6: Final answer
    x = 206.56

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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.