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Finding the Fourth Proportional to 638.92, 881.66 and 359.20

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Solution

The fourth proportional to 638.92, 881.66 and 359.20 is: 495.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.92 : 881.66 = 359.20 : x
  2. Step 2: Convert to fraction form
    638.92/881.66 = 359.20/x
  3. Step 3: Cross multiply
    638.92x = 881.66 × 359.20
  4. Step 4: Simplify right side
    638.92x = 316,687.86
  5. Step 5: Solve for x
    x = 316,687.86/638.92
  6. Step 6: Final answer
    x = 495.66

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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.