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Finding the Fourth Proportional to 429.95, 645.02 and 121.79

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Solution

The fourth proportional to 429.95, 645.02 and 121.79 is: 182.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.95 : 645.02 = 121.79 : x
  2. Step 2: Convert to fraction form
    429.95/645.02 = 121.79/x
  3. Step 3: Cross multiply
    429.95x = 645.02 × 121.79
  4. Step 4: Simplify right side
    429.95x = 78,553.15
  5. Step 5: Solve for x
    x = 78,553.15/429.95
  6. Step 6: Final answer
    x = 182.71

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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.