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Finding the Fourth Proportional to 279.46, 385.85 and 209.68

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Solution

The fourth proportional to 279.46, 385.85 and 209.68 is: 289.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.46 : 385.85 = 209.68 : x
  2. Step 2: Convert to fraction form
    279.46/385.85 = 209.68/x
  3. Step 3: Cross multiply
    279.46x = 385.85 × 209.68
  4. Step 4: Simplify right side
    279.46x = 80,905.03
  5. Step 5: Solve for x
    x = 80,905.03/279.46
  6. Step 6: Final answer
    x = 289.50

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.