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Finding the Fourth Proportional to 643.29, 888.20 and 394.94

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Solution

The fourth proportional to 643.29, 888.20 and 394.94 is: 545.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.29 : 888.20 = 394.94 : x
  2. Step 2: Convert to fraction form
    643.29/888.20 = 394.94/x
  3. Step 3: Cross multiply
    643.29x = 888.20 × 394.94
  4. Step 4: Simplify right side
    643.29x = 350,787.43
  5. Step 5: Solve for x
    x = 350,787.43/643.29
  6. Step 6: Final answer
    x = 545.31

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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.