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Finding the Fourth Proportional to 165.78, 249.75 and 129.87

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Solution

The fourth proportional to 165.78, 249.75 and 129.87 is: 195.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    165.78 : 249.75 = 129.87 : x
  2. Step 2: Convert to fraction form
    165.78/249.75 = 129.87/x
  3. Step 3: Cross multiply
    165.78x = 249.75 × 129.87
  4. Step 4: Simplify right side
    165.78x = 32,435.03
  5. Step 5: Solve for x
    x = 32,435.03/165.78
  6. Step 6: Final answer
    x = 195.65

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.