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Finding the Fourth Proportional to 278.43, 384.87 and 219.78

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Solution

The fourth proportional to 278.43, 384.87 and 219.78 is: 303.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.43 : 384.87 = 219.78 : x
  2. Step 2: Convert to fraction form
    278.43/384.87 = 219.78/x
  3. Step 3: Cross multiply
    278.43x = 384.87 × 219.78
  4. Step 4: Simplify right side
    278.43x = 84,586.73
  5. Step 5: Solve for x
    x = 84,586.73/278.43
  6. Step 6: Final answer
    x = 303.80

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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.