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Finding the Fourth Proportional to 280.61, 420.14 and 211.92

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Solution

The fourth proportional to 280.61, 420.14 and 211.92 is: 317.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.61 : 420.14 = 211.92 : x
  2. Step 2: Convert to fraction form
    280.61/420.14 = 211.92/x
  3. Step 3: Cross multiply
    280.61x = 420.14 × 211.92
  4. Step 4: Simplify right side
    280.61x = 89,035.01
  5. Step 5: Solve for x
    x = 89,035.01/280.61
  6. Step 6: Final answer
    x = 317.30

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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.