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Finding the Fourth Proportional to 280.92, 420.42 and 256.58

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Solution

The fourth proportional to 280.92, 420.42 and 256.58 is: 383.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.92 : 420.42 = 256.58 : x
  2. Step 2: Convert to fraction form
    280.92/420.42 = 256.58/x
  3. Step 3: Cross multiply
    280.92x = 420.42 × 256.58
  4. Step 4: Simplify right side
    280.92x = 107,871.36
  5. Step 5: Solve for x
    x = 107,871.36/280.92
  6. Step 6: Final answer
    x = 383.99

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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.