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Finding the Fourth Proportional to 428.36, 590.56 and 280.76

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Solution

The fourth proportional to 428.36, 590.56 and 280.76 is: 387.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.36 : 590.56 = 280.76 : x
  2. Step 2: Convert to fraction form
    428.36/590.56 = 280.76/x
  3. Step 3: Cross multiply
    428.36x = 590.56 × 280.76
  4. Step 4: Simplify right side
    428.36x = 165,805.63
  5. Step 5: Solve for x
    x = 165,805.63/428.36
  6. Step 6: Final answer
    x = 387.07

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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.