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Finding the Fourth Proportional to 385.32, 577.82 and 128.76

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Solution

The fourth proportional to 385.32, 577.82 and 128.76 is: 193.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.32 : 577.82 = 128.76 : x
  2. Step 2: Convert to fraction form
    385.32/577.82 = 128.76/x
  3. Step 3: Cross multiply
    385.32x = 577.82 × 128.76
  4. Step 4: Simplify right side
    385.32x = 74,400.10
  5. Step 5: Solve for x
    x = 74,400.10/385.32
  6. Step 6: Final answer
    x = 193.09

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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.