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Finding the Fourth Proportional to 384.78, 531.04 and 280.30

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Solution

The fourth proportional to 384.78, 531.04 and 280.30 is: 386.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    384.78 : 531.04 = 280.30 : x
  2. Step 2: Convert to fraction form
    384.78/531.04 = 280.30/x
  3. Step 3: Cross multiply
    384.78x = 531.04 × 280.30
  4. Step 4: Simplify right side
    384.78x = 148,850.51
  5. Step 5: Solve for x
    x = 148,850.51/384.78
  6. Step 6: Final answer
    x = 386.85

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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.