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Finding the Fourth Proportional to 278.68, 384.30 and 209.56

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Solution

The fourth proportional to 278.68, 384.30 and 209.56 is: 288.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.68 : 384.30 = 209.56 : x
  2. Step 2: Convert to fraction form
    278.68/384.30 = 209.56/x
  3. Step 3: Cross multiply
    278.68x = 384.30 × 209.56
  4. Step 4: Simplify right side
    278.68x = 80,533.91
  5. Step 5: Solve for x
    x = 80,533.91/278.68
  6. Step 6: Final answer
    x = 288.98

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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.