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Finding the Fourth Proportional to 639.57, 883.05 and 418.83

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Solution

The fourth proportional to 639.57, 883.05 and 418.83 is: 578.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.57 : 883.05 = 418.83 : x
  2. Step 2: Convert to fraction form
    639.57/883.05 = 418.83/x
  3. Step 3: Cross multiply
    639.57x = 883.05 × 418.83
  4. Step 4: Simplify right side
    639.57x = 369,847.83
  5. Step 5: Solve for x
    x = 369,847.83/639.57
  6. Step 6: Final answer
    x = 578.28

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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.