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Finding the Fourth Proportional to 426.81, 639.83 and 207.30

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Solution

The fourth proportional to 426.81, 639.83 and 207.30 is: 310.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.81 : 639.83 = 207.30 : x
  2. Step 2: Convert to fraction form
    426.81/639.83 = 207.30/x
  3. Step 3: Cross multiply
    426.81x = 639.83 × 207.30
  4. Step 4: Simplify right side
    426.81x = 132,636.76
  5. Step 5: Solve for x
    x = 132,636.76/426.81
  6. Step 6: Final answer
    x = 310.76

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.