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Finding the Fourth Proportional to 605.20, 907.92 and 280.72

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Solution

The fourth proportional to 605.20, 907.92 and 280.72 is: 421.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    605.20 : 907.92 = 280.72 : x
  2. Step 2: Convert to fraction form
    605.20/907.92 = 280.72/x
  3. Step 3: Cross multiply
    605.20x = 907.92 × 280.72
  4. Step 4: Simplify right side
    605.20x = 254,871.30
  5. Step 5: Solve for x
    x = 254,871.30/605.20
  6. Step 6: Final answer
    x = 421.14

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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.