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Finding the Fourth Proportional to 426.09, 638.56 and 261.04

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Solution

The fourth proportional to 426.09, 638.56 and 261.04 is: 391.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.09 : 638.56 = 261.04 : x
  2. Step 2: Convert to fraction form
    426.09/638.56 = 261.04/x
  3. Step 3: Cross multiply
    426.09x = 638.56 × 261.04
  4. Step 4: Simplify right side
    426.09x = 166,689.70
  5. Step 5: Solve for x
    x = 166,689.70/426.09
  6. Step 6: Final answer
    x = 391.21

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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.