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Finding the Fourth Proportional to 426.25, 638.76 and 209.98

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Solution

The fourth proportional to 426.25, 638.76 and 209.98 is: 314.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.25 : 638.76 = 209.98 : x
  2. Step 2: Convert to fraction form
    426.25/638.76 = 209.98/x
  3. Step 3: Cross multiply
    426.25x = 638.76 × 209.98
  4. Step 4: Simplify right side
    426.25x = 134,123.63
  5. Step 5: Solve for x
    x = 134,123.63/426.25
  6. Step 6: Final answer
    x = 314.66

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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.