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Finding the Fourth Proportional to 458.48, 687.80 and 239.20

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Solution

The fourth proportional to 458.48, 687.80 and 239.20 is: 358.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    458.48 : 687.80 = 239.20 : x
  2. Step 2: Convert to fraction form
    458.48/687.80 = 239.20/x
  3. Step 3: Cross multiply
    458.48x = 687.80 × 239.20
  4. Step 4: Simplify right side
    458.48x = 164,520.64
  5. Step 5: Solve for x
    x = 164,520.64/458.48
  6. Step 6: Final answer
    x = 358.84

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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.