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Finding the Fourth Proportional to 279.59, 385.63 and 209.90

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Solution

The fourth proportional to 279.59, 385.63 and 209.90 is: 289.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.59 : 385.63 = 209.90 : x
  2. Step 2: Convert to fraction form
    279.59/385.63 = 209.90/x
  3. Step 3: Cross multiply
    279.59x = 385.63 × 209.90
  4. Step 4: Simplify right side
    279.59x = 80,944.18
  5. Step 5: Solve for x
    x = 80,944.18/279.59
  6. Step 6: Final answer
    x = 289.52

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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.