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Finding the Fourth Proportional to 631.90, 871.61 and 408.12

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Solution

The fourth proportional to 631.90, 871.61 and 408.12 is: 562.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.90 : 871.61 = 408.12 : x
  2. Step 2: Convert to fraction form
    631.90/871.61 = 408.12/x
  3. Step 3: Cross multiply
    631.90x = 871.61 × 408.12
  4. Step 4: Simplify right side
    631.90x = 355,719.43
  5. Step 5: Solve for x
    x = 355,719.43/631.90
  6. Step 6: Final answer
    x = 562.94

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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.