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Finding the Fourth Proportional to 82.40, 123.07 and 68.87

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Solution

The fourth proportional to 82.40, 123.07 and 68.87 is: 102.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    82.40 : 123.07 = 68.87 : x
  2. Step 2: Convert to fraction form
    82.40/123.07 = 68.87/x
  3. Step 3: Cross multiply
    82.40x = 123.07 × 68.87
  4. Step 4: Simplify right side
    82.40x = 8,475.83
  5. Step 5: Solve for x
    x = 8,475.83/82.40
  6. Step 6: Final answer
    x = 102.86

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.