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Finding the Fourth Proportional to 658.40, 908.51 and 392.72

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Solution

The fourth proportional to 658.40, 908.51 and 392.72 is: 541.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.40 : 908.51 = 392.72 : x
  2. Step 2: Convert to fraction form
    658.40/908.51 = 392.72/x
  3. Step 3: Cross multiply
    658.40x = 908.51 × 392.72
  4. Step 4: Simplify right side
    658.40x = 356,783.54
  5. Step 5: Solve for x
    x = 356,783.54/658.40
  6. Step 6: Final answer
    x = 541.90

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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.