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Finding the Fourth Proportional to 625.10, 861.75 and 428.30

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Solution

The fourth proportional to 625.10, 861.75 and 428.30 is: 590.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    625.10 : 861.75 = 428.30 : x
  2. Step 2: Convert to fraction form
    625.10/861.75 = 428.30/x
  3. Step 3: Cross multiply
    625.10x = 861.75 × 428.30
  4. Step 4: Simplify right side
    625.10x = 369,087.53
  5. Step 5: Solve for x
    x = 369,087.53/625.10
  6. Step 6: Final answer
    x = 590.45

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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.