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Finding the Fourth Proportional to 647.90, 893.67 and 398.97

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Solution

The fourth proportional to 647.90, 893.67 and 398.97 is: 550.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.90 : 893.67 = 398.97 : x
  2. Step 2: Convert to fraction form
    647.90/893.67 = 398.97/x
  3. Step 3: Cross multiply
    647.90x = 893.67 × 398.97
  4. Step 4: Simplify right side
    647.90x = 356,545.53
  5. Step 5: Solve for x
    x = 356,545.53/647.90
  6. Step 6: Final answer
    x = 550.31

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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.