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Finding the Fourth Proportional to 645.10, 966.30 and 426.40

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Solution

The fourth proportional to 645.10, 966.30 and 426.40 is: 638.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.10 : 966.30 = 426.40 : x
  2. Step 2: Convert to fraction form
    645.10/966.30 = 426.40/x
  3. Step 3: Cross multiply
    645.10x = 966.30 × 426.40
  4. Step 4: Simplify right side
    645.10x = 412,030.32
  5. Step 5: Solve for x
    x = 412,030.32/645.10
  6. Step 6: Final answer
    x = 638.71

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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.