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Finding the Fourth Proportional to 426.48, 639.38 and 209.94

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Solution

The fourth proportional to 426.48, 639.38 and 209.94 is: 314.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.48 : 639.38 = 209.94 : x
  2. Step 2: Convert to fraction form
    426.48/639.38 = 209.94/x
  3. Step 3: Cross multiply
    426.48x = 639.38 × 209.94
  4. Step 4: Simplify right side
    426.48x = 134,230.39
  5. Step 5: Solve for x
    x = 134,230.39/426.48
  6. Step 6: Final answer
    x = 314.74

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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.