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Finding the Fourth Proportional to 629.20, 861.50 and 629.20

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Solution

The fourth proportional to 629.20, 861.50 and 629.20 is: 861.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    629.20 : 861.50 = 629.20 : x
  2. Step 2: Convert to fraction form
    629.20/861.50 = 629.20/x
  3. Step 3: Cross multiply
    629.20x = 861.50 × 629.20
  4. Step 4: Simplify right side
    629.20x = 542,055.80
  5. Step 5: Solve for x
    x = 542,055.80/629.20
  6. Step 6: Final answer
    x = 861.50

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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.