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Finding the Fourth Proportional to 428.09, 590.73 and 280.49

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Solution

The fourth proportional to 428.09, 590.73 and 280.49 is: 387.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.09 : 590.73 = 280.49 : x
  2. Step 2: Convert to fraction form
    428.09/590.73 = 280.49/x
  3. Step 3: Cross multiply
    428.09x = 590.73 × 280.49
  4. Step 4: Simplify right side
    428.09x = 165,693.86
  5. Step 5: Solve for x
    x = 165,693.86/428.09
  6. Step 6: Final answer
    x = 387.05

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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.