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Finding the Fourth Proportional to 458.16, 687.20 and 129.08

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Solution

The fourth proportional to 458.16, 687.20 and 129.08 is: 193.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    458.16 : 687.20 = 129.08 : x
  2. Step 2: Convert to fraction form
    458.16/687.20 = 129.08/x
  3. Step 3: Cross multiply
    458.16x = 687.20 × 129.08
  4. Step 4: Simplify right side
    458.16x = 88,701.71
  5. Step 5: Solve for x
    x = 88,701.71/458.16
  6. Step 6: Final answer
    x = 193.60

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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.