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Finding the Fourth Proportional to 278.78, 384.76 and 205.30

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Solution

The fourth proportional to 278.78, 384.76 and 205.30 is: 283.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.78 : 384.76 = 205.30 : x
  2. Step 2: Convert to fraction form
    278.78/384.76 = 205.30/x
  3. Step 3: Cross multiply
    278.78x = 384.76 × 205.30
  4. Step 4: Simplify right side
    278.78x = 78,991.23
  5. Step 5: Solve for x
    x = 78,991.23/278.78
  6. Step 6: Final answer
    x = 283.35

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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.