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Finding the Fourth Proportional to 641.44, 885.27 and 392.79

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Solution

The fourth proportional to 641.44, 885.27 and 392.79 is: 542.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.44 : 885.27 = 392.79 : x
  2. Step 2: Convert to fraction form
    641.44/885.27 = 392.79/x
  3. Step 3: Cross multiply
    641.44x = 885.27 × 392.79
  4. Step 4: Simplify right side
    641.44x = 347,725.20
  5. Step 5: Solve for x
    x = 347,725.20/641.44
  6. Step 6: Final answer
    x = 542.10

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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.