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Finding the Fourth Proportional to 280.50, 387.17 and 247.86

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Solution

The fourth proportional to 280.50, 387.17 and 247.86 is: 342.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.50 : 387.17 = 247.86 : x
  2. Step 2: Convert to fraction form
    280.50/387.17 = 247.86/x
  3. Step 3: Cross multiply
    280.50x = 387.17 × 247.86
  4. Step 4: Simplify right side
    280.50x = 95,963.96
  5. Step 5: Solve for x
    x = 95,963.96/280.50
  6. Step 6: Final answer
    x = 342.12

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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.