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Finding the Fourth Proportional to 88.20, 131.82 and 68.70

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Solution

The fourth proportional to 88.20, 131.82 and 68.70 is: 102.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    88.20 : 131.82 = 68.70 : x
  2. Step 2: Convert to fraction form
    88.20/131.82 = 68.70/x
  3. Step 3: Cross multiply
    88.20x = 131.82 × 68.70
  4. Step 4: Simplify right side
    88.20x = 9,056.03
  5. Step 5: Solve for x
    x = 9,056.03/88.20
  6. Step 6: Final answer
    x = 102.68

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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.