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Finding the Fourth Proportional to 458.57, 687.85 and 129.51

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Solution

The fourth proportional to 458.57, 687.85 and 129.51 is: 194.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    458.57 : 687.85 = 129.51 : x
  2. Step 2: Convert to fraction form
    458.57/687.85 = 129.51/x
  3. Step 3: Cross multiply
    458.57x = 687.85 × 129.51
  4. Step 4: Simplify right side
    458.57x = 89,083.45
  5. Step 5: Solve for x
    x = 89,083.45/458.57
  6. Step 6: Final answer
    x = 194.26

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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.