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Finding the Fourth Proportional to 380.76, 571.12 and 137.28

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Solution

The fourth proportional to 380.76, 571.12 and 137.28 is: 205.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.76 : 571.12 = 137.28 : x
  2. Step 2: Convert to fraction form
    380.76/571.12 = 137.28/x
  3. Step 3: Cross multiply
    380.76x = 571.12 × 137.28
  4. Step 4: Simplify right side
    380.76x = 78,403.35
  5. Step 5: Solve for x
    x = 78,403.35/380.76
  6. Step 6: Final answer
    x = 205.91

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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.