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Finding the Fourth Proportional to 640.78, 884.02 and 404.67

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Solution

The fourth proportional to 640.78, 884.02 and 404.67 is: 558.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.78 : 884.02 = 404.67 : x
  2. Step 2: Convert to fraction form
    640.78/884.02 = 404.67/x
  3. Step 3: Cross multiply
    640.78x = 884.02 × 404.67
  4. Step 4: Simplify right side
    640.78x = 357,736.37
  5. Step 5: Solve for x
    x = 357,736.37/640.78
  6. Step 6: Final answer
    x = 558.28

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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.