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Finding the Fourth Proportional to 130.31, 179.78 and 81.17

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Solution

The fourth proportional to 130.31, 179.78 and 81.17 is: 111.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    130.31 : 179.78 = 81.17 : x
  2. Step 2: Convert to fraction form
    130.31/179.78 = 81.17/x
  3. Step 3: Cross multiply
    130.31x = 179.78 × 81.17
  4. Step 4: Simplify right side
    130.31x = 14,591.44
  5. Step 5: Solve for x
    x = 14,591.44/130.31
  6. Step 6: Final answer
    x = 111.98

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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.