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Finding the Fourth Proportional to 630.08, 869.12 and 396.80

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Solution

The fourth proportional to 630.08, 869.12 and 396.80 is: 547.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.08 : 869.12 = 396.80 : x
  2. Step 2: Convert to fraction form
    630.08/869.12 = 396.80/x
  3. Step 3: Cross multiply
    630.08x = 869.12 × 396.80
  4. Step 4: Simplify right side
    630.08x = 344,866.82
  5. Step 5: Solve for x
    x = 344,866.82/630.08
  6. Step 6: Final answer
    x = 547.34

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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.