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Finding the Fourth Proportional to 631.54, 871.44 and 421.85

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Solution

The fourth proportional to 631.54, 871.44 and 421.85 is: 582.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.54 : 871.44 = 421.85 : x
  2. Step 2: Convert to fraction form
    631.54/871.44 = 421.85/x
  3. Step 3: Cross multiply
    631.54x = 871.44 × 421.85
  4. Step 4: Simplify right side
    631.54x = 367,616.96
  5. Step 5: Solve for x
    x = 367,616.96/631.54
  6. Step 6: Final answer
    x = 582.10

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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.