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Finding the Fourth Proportional to 84.31, 126.49 and 38.69

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Solution

The fourth proportional to 84.31, 126.49 and 38.69 is: 58.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    84.31 : 126.49 = 38.69 : x
  2. Step 2: Convert to fraction form
    84.31/126.49 = 38.69/x
  3. Step 3: Cross multiply
    84.31x = 126.49 × 38.69
  4. Step 4: Simplify right side
    84.31x = 4,894.03
  5. Step 5: Solve for x
    x = 4,894.03/84.31
  6. Step 6: Final answer
    x = 58.05

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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.