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Finding the Fourth Proportional to 640.89, 884.12 and 392.13

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Solution

The fourth proportional to 640.89, 884.12 and 392.13 is: 540.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.89 : 884.12 = 392.13 : x
  2. Step 2: Convert to fraction form
    640.89/884.12 = 392.13/x
  3. Step 3: Cross multiply
    640.89x = 884.12 × 392.13
  4. Step 4: Simplify right side
    640.89x = 346,688.01
  5. Step 5: Solve for x
    x = 346,688.01/640.89
  6. Step 6: Final answer
    x = 540.95

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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.