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Finding the Fourth Proportional to 631.38, 871.28 and 351.61

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Solution

The fourth proportional to 631.38, 871.28 and 351.61 is: 485.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.38 : 871.28 = 351.61 : x
  2. Step 2: Convert to fraction form
    631.38/871.28 = 351.61/x
  3. Step 3: Cross multiply
    631.38x = 871.28 × 351.61
  4. Step 4: Simplify right side
    631.38x = 306,346.40
  5. Step 5: Solve for x
    x = 306,346.40/631.38
  6. Step 6: Final answer
    x = 485.21

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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.