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Finding the Fourth Proportional to 428.97, 638.63 and 426.93

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Solution

The fourth proportional to 428.97, 638.63 and 426.93 is: 635.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.97 : 638.63 = 426.93 : x
  2. Step 2: Convert to fraction form
    428.97/638.63 = 426.93/x
  3. Step 3: Cross multiply
    428.97x = 638.63 × 426.93
  4. Step 4: Simplify right side
    428.97x = 272,648.17
  5. Step 5: Solve for x
    x = 272,648.17/428.97
  6. Step 6: Final answer
    x = 635.59

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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.