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Finding the Fourth Proportional to 278.78, 418.27 and 186.61

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Solution

The fourth proportional to 278.78, 418.27 and 186.61 is: 279.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.78 : 418.27 = 186.61 : x
  2. Step 2: Convert to fraction form
    278.78/418.27 = 186.61/x
  3. Step 3: Cross multiply
    278.78x = 418.27 × 186.61
  4. Step 4: Simplify right side
    278.78x = 78,052.55
  5. Step 5: Solve for x
    x = 78,052.55/278.78
  6. Step 6: Final answer
    x = 279.98

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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.