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Finding the Fourth Proportional to 641.08, 878.28 and 617.08

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Solution

The fourth proportional to 641.08, 878.28 and 617.08 is: 845.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.08 : 878.28 = 617.08 : x
  2. Step 2: Convert to fraction form
    641.08/878.28 = 617.08/x
  3. Step 3: Cross multiply
    641.08x = 878.28 × 617.08
  4. Step 4: Simplify right side
    641.08x = 541,965.94
  5. Step 5: Solve for x
    x = 541,965.94/641.08
  6. Step 6: Final answer
    x = 845.40

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.