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Finding the Fourth Proportional to 458.32, 687.12 and 320.80

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Solution

The fourth proportional to 458.32, 687.12 and 320.80 is: 480.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    458.32 : 687.12 = 320.80 : x
  2. Step 2: Convert to fraction form
    458.32/687.12 = 320.80/x
  3. Step 3: Cross multiply
    458.32x = 687.12 × 320.80
  4. Step 4: Simplify right side
    458.32x = 220,428.10
  5. Step 5: Solve for x
    x = 220,428.10/458.32
  6. Step 6: Final answer
    x = 480.95

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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.