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Finding the Fourth Proportional to 630.86, 869.84 and 431.78

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Solution

The fourth proportional to 630.86, 869.84 and 431.78 is: 595.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.86 : 869.84 = 431.78 : x
  2. Step 2: Convert to fraction form
    630.86/869.84 = 431.78/x
  3. Step 3: Cross multiply
    630.86x = 869.84 × 431.78
  4. Step 4: Simplify right side
    630.86x = 375,579.53
  5. Step 5: Solve for x
    x = 375,579.53/630.86
  6. Step 6: Final answer
    x = 595.35

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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.