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Finding the Fourth Proportional to 630.31, 869.55 and 420.29

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Solution

The fourth proportional to 630.31, 869.55 and 420.29 is: 579.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.31 : 869.55 = 420.29 : x
  2. Step 2: Convert to fraction form
    630.31/869.55 = 420.29/x
  3. Step 3: Cross multiply
    630.31x = 869.55 × 420.29
  4. Step 4: Simplify right side
    630.31x = 365,458.82
  5. Step 5: Solve for x
    x = 365,458.82/630.31
  6. Step 6: Final answer
    x = 579.81

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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.