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Finding the Fourth Proportional to 640.22, 887.57 and 617.69

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Solution

The fourth proportional to 640.22, 887.57 and 617.69 is: 856.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.22 : 887.57 = 617.69 : x
  2. Step 2: Convert to fraction form
    640.22/887.57 = 617.69/x
  3. Step 3: Cross multiply
    640.22x = 887.57 × 617.69
  4. Step 4: Simplify right side
    640.22x = 548,244.56
  5. Step 5: Solve for x
    x = 548,244.56/640.22
  6. Step 6: Final answer
    x = 856.34

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.