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Finding the Fourth Proportional to 528.31, 791.80 and 280.90

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Solution

The fourth proportional to 528.31, 791.80 and 280.90 is: 421.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.31 : 791.80 = 280.90 : x
  2. Step 2: Convert to fraction form
    528.31/791.80 = 280.90/x
  3. Step 3: Cross multiply
    528.31x = 791.80 × 280.90
  4. Step 4: Simplify right side
    528.31x = 222,416.91
  5. Step 5: Solve for x
    x = 222,416.91/528.31
  6. Step 6: Final answer
    x = 421.00

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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.