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Finding the Fourth Proportional to 423.88, 634.98 and 206.80

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Solution

The fourth proportional to 423.88, 634.98 and 206.80 is: 309.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    423.88 : 634.98 = 206.80 : x
  2. Step 2: Convert to fraction form
    423.88/634.98 = 206.80/x
  3. Step 3: Cross multiply
    423.88x = 634.98 × 206.80
  4. Step 4: Simplify right side
    423.88x = 131,313.86
  5. Step 5: Solve for x
    x = 131,313.86/423.88
  6. Step 6: Final answer
    x = 309.79

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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.