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Finding the Fourth Proportional to 278.20, 384.05 and 215.89

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Solution

The fourth proportional to 278.20, 384.05 and 215.89 is: 298.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.20 : 384.05 = 215.89 : x
  2. Step 2: Convert to fraction form
    278.20/384.05 = 215.89/x
  3. Step 3: Cross multiply
    278.20x = 384.05 × 215.89
  4. Step 4: Simplify right side
    278.20x = 82,912.55
  5. Step 5: Solve for x
    x = 82,912.55/278.20
  6. Step 6: Final answer
    x = 298.03

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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.