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Finding the Fourth Proportional to 458.61, 687.38 and 320.91

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Solution

The fourth proportional to 458.61, 687.38 and 320.91 is: 480.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    458.61 : 687.38 = 320.91 : x
  2. Step 2: Convert to fraction form
    458.61/687.38 = 320.91/x
  3. Step 3: Cross multiply
    458.61x = 687.38 × 320.91
  4. Step 4: Simplify right side
    458.61x = 220,585.51
  5. Step 5: Solve for x
    x = 220,585.51/458.61
  6. Step 6: Final answer
    x = 480.99

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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.