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Finding the Fourth Proportional to 428.31, 637.28 and 426.81

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Solution

The fourth proportional to 428.31, 637.28 and 426.81 is: 635.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.31 : 637.28 = 426.81 : x
  2. Step 2: Convert to fraction form
    428.31/637.28 = 426.81/x
  3. Step 3: Cross multiply
    428.31x = 637.28 × 426.81
  4. Step 4: Simplify right side
    428.31x = 271,998.54
  5. Step 5: Solve for x
    x = 271,998.54/428.31
  6. Step 6: Final answer
    x = 635.05

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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.