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Finding the Fourth Proportional to 279.72, 385.56 and 209.66

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Solution

The fourth proportional to 279.72, 385.56 and 209.66 is: 288.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.72 : 385.56 = 209.66 : x
  2. Step 2: Convert to fraction form
    279.72/385.56 = 209.66/x
  3. Step 3: Cross multiply
    279.72x = 385.56 × 209.66
  4. Step 4: Simplify right side
    279.72x = 80,834.58
  5. Step 5: Solve for x
    x = 80,834.58/279.72
  6. Step 6: Final answer
    x = 288.98

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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.