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Finding the Fourth Proportional to 458.12, 687.02 and 211.30

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Solution

The fourth proportional to 458.12, 687.02 and 211.30 is: 316.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    458.12 : 687.02 = 211.30 : x
  2. Step 2: Convert to fraction form
    458.12/687.02 = 211.30/x
  3. Step 3: Cross multiply
    458.12x = 687.02 × 211.30
  4. Step 4: Simplify right side
    458.12x = 145,167.33
  5. Step 5: Solve for x
    x = 145,167.33/458.12
  6. Step 6: Final answer
    x = 316.88

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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.