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Finding the Fourth Proportional to 630.20, 945.31 and 386.56

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Solution

The fourth proportional to 630.20, 945.31 and 386.56 is: 579.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.20 : 945.31 = 386.56 : x
  2. Step 2: Convert to fraction form
    630.20/945.31 = 386.56/x
  3. Step 3: Cross multiply
    630.20x = 945.31 × 386.56
  4. Step 4: Simplify right side
    630.20x = 365,419.03
  5. Step 5: Solve for x
    x = 365,419.03/630.20
  6. Step 6: Final answer
    x = 579.85

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.