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Finding the Fourth Proportional to 631.28, 871.11 and 355.28

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Solution

The fourth proportional to 631.28, 871.11 and 355.28 is: 490.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.28 : 871.11 = 355.28 : x
  2. Step 2: Convert to fraction form
    631.28/871.11 = 355.28/x
  3. Step 3: Cross multiply
    631.28x = 871.11 × 355.28
  4. Step 4: Simplify right side
    631.28x = 309,487.96
  5. Step 5: Solve for x
    x = 309,487.96/631.28
  6. Step 6: Final answer
    x = 490.25

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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.