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Finding the Fourth Proportional to 620.34, 855.09 and 495.78

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Solution

The fourth proportional to 620.34, 855.09 and 495.78 is: 683.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.34 : 855.09 = 495.78 : x
  2. Step 2: Convert to fraction form
    620.34/855.09 = 495.78/x
  3. Step 3: Cross multiply
    620.34x = 855.09 × 495.78
  4. Step 4: Simplify right side
    620.34x = 423,936.52
  5. Step 5: Solve for x
    x = 423,936.52/620.34
  6. Step 6: Final answer
    x = 683.39

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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.