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Finding the Fourth Proportional to 641.60, 884.62 and 420.17

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Solution

The fourth proportional to 641.60, 884.62 and 420.17 is: 579.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.60 : 884.62 = 420.17 : x
  2. Step 2: Convert to fraction form
    641.60/884.62 = 420.17/x
  3. Step 3: Cross multiply
    641.60x = 884.62 × 420.17
  4. Step 4: Simplify right side
    641.60x = 371,691.86
  5. Step 5: Solve for x
    x = 371,691.86/641.60
  6. Step 6: Final answer
    x = 579.32

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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.