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Finding the Fourth Proportional to 68.74, 103.02 and 39.87

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Solution

The fourth proportional to 68.74, 103.02 and 39.87 is: 59.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.74 : 103.02 = 39.87 : x
  2. Step 2: Convert to fraction form
    68.74/103.02 = 39.87/x
  3. Step 3: Cross multiply
    68.74x = 103.02 × 39.87
  4. Step 4: Simplify right side
    68.74x = 4,107.41
  5. Step 5: Solve for x
    x = 4,107.41/68.74
  6. Step 6: Final answer
    x = 59.75

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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.