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Finding the Fourth Proportional to 628.86, 867.84 and 392.91

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Solution

The fourth proportional to 628.86, 867.84 and 392.91 is: 542.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.86 : 867.84 = 392.91 : x
  2. Step 2: Convert to fraction form
    628.86/867.84 = 392.91/x
  3. Step 3: Cross multiply
    628.86x = 867.84 × 392.91
  4. Step 4: Simplify right side
    628.86x = 340,983.01
  5. Step 5: Solve for x
    x = 340,983.01/628.86
  6. Step 6: Final answer
    x = 542.22

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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.