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Finding the Fourth Proportional to 428.52, 638.25 and 426.45

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Solution

The fourth proportional to 428.52, 638.25 and 426.45 is: 635.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.52 : 638.25 = 426.45 : x
  2. Step 2: Convert to fraction form
    428.52/638.25 = 426.45/x
  3. Step 3: Cross multiply
    428.52x = 638.25 × 426.45
  4. Step 4: Simplify right side
    428.52x = 272,181.71
  5. Step 5: Solve for x
    x = 272,181.71/428.52
  6. Step 6: Final answer
    x = 635.17

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.