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Finding the Fourth Proportional to 68.56, 102.90 and 55.12

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Solution

The fourth proportional to 68.56, 102.90 and 55.12 is: 82.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.56 : 102.90 = 55.12 : x
  2. Step 2: Convert to fraction form
    68.56/102.90 = 55.12/x
  3. Step 3: Cross multiply
    68.56x = 102.90 × 55.12
  4. Step 4: Simplify right side
    68.56x = 5,671.06
  5. Step 5: Solve for x
    x = 5,671.06/68.56
  6. Step 6: Final answer
    x = 82.72

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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.