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Finding the Fourth Proportional to 279.55, 385.83 and 209.96

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Solution

The fourth proportional to 279.55, 385.83 and 209.96 is: 289.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.55 : 385.83 = 209.96 : x
  2. Step 2: Convert to fraction form
    279.55/385.83 = 209.96/x
  3. Step 3: Cross multiply
    279.55x = 385.83 × 209.96
  4. Step 4: Simplify right side
    279.55x = 81,008.38
  5. Step 5: Solve for x
    x = 81,008.38/279.55
  6. Step 6: Final answer
    x = 289.78

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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.