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Finding the Fourth Proportional to 643.78, 892.09 and 604.77

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Solution

The fourth proportional to 643.78, 892.09 and 604.77 is: 838.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.78 : 892.09 = 604.77 : x
  2. Step 2: Convert to fraction form
    643.78/892.09 = 604.77/x
  3. Step 3: Cross multiply
    643.78x = 892.09 × 604.77
  4. Step 4: Simplify right side
    643.78x = 539,509.27
  5. Step 5: Solve for x
    x = 539,509.27/643.78
  6. Step 6: Final answer
    x = 838.03

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.