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Finding the Fourth Proportional to 83.21, 125.02 and 78.61

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Solution

The fourth proportional to 83.21, 125.02 and 78.61 is: 118.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    83.21 : 125.02 = 78.61 : x
  2. Step 2: Convert to fraction form
    83.21/125.02 = 78.61/x
  3. Step 3: Cross multiply
    83.21x = 125.02 × 78.61
  4. Step 4: Simplify right side
    83.21x = 9,826.80
  5. Step 5: Solve for x
    x = 9,826.80/83.21
  6. Step 6: Final answer
    x = 118.10

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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.