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Finding the Fourth Proportional to 643.98, 888.41 and 395.29

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Solution

The fourth proportional to 643.98, 888.41 and 395.29 is: 545.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.98 : 888.41 = 395.29 : x
  2. Step 2: Convert to fraction form
    643.98/888.41 = 395.29/x
  3. Step 3: Cross multiply
    643.98x = 888.41 × 395.29
  4. Step 4: Simplify right side
    643.98x = 351,179.59
  5. Step 5: Solve for x
    x = 351,179.59/643.98
  6. Step 6: Final answer
    x = 545.33

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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.