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Finding the Fourth Proportional to 280.79, 387.65 and 213.88

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Solution

The fourth proportional to 280.79, 387.65 and 213.88 is: 295.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.79 : 387.65 = 213.88 : x
  2. Step 2: Convert to fraction form
    280.79/387.65 = 213.88/x
  3. Step 3: Cross multiply
    280.79x = 387.65 × 213.88
  4. Step 4: Simplify right side
    280.79x = 82,910.08
  5. Step 5: Solve for x
    x = 82,910.08/280.79
  6. Step 6: Final answer
    x = 295.27

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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.