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Finding the Fourth Proportional to 102.70, 141.30 and 80.82

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Solution

The fourth proportional to 102.70, 141.30 and 80.82 is: 111.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    102.70 : 141.30 = 80.82 : x
  2. Step 2: Convert to fraction form
    102.70/141.30 = 80.82/x
  3. Step 3: Cross multiply
    102.70x = 141.30 × 80.82
  4. Step 4: Simplify right side
    102.70x = 11,419.87
  5. Step 5: Solve for x
    x = 11,419.87/102.70
  6. Step 6: Final answer
    x = 111.20

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.