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Finding the Fourth Proportional to 428.10, 590.69 and 280.64

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Solution

The fourth proportional to 428.10, 590.69 and 280.64 is: 387.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.10 : 590.69 = 280.64 : x
  2. Step 2: Convert to fraction form
    428.10/590.69 = 280.64/x
  3. Step 3: Cross multiply
    428.10x = 590.69 × 280.64
  4. Step 4: Simplify right side
    428.10x = 165,766.88
  5. Step 5: Solve for x
    x = 165,766.88/428.10
  6. Step 6: Final answer
    x = 387.22

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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.