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Finding the Fourth Proportional to 131.21, 181.17 and 115.85

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Solution

The fourth proportional to 131.21, 181.17 and 115.85 is: 159.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    131.21 : 181.17 = 115.85 : x
  2. Step 2: Convert to fraction form
    131.21/181.17 = 115.85/x
  3. Step 3: Cross multiply
    131.21x = 181.17 × 115.85
  4. Step 4: Simplify right side
    131.21x = 20,988.54
  5. Step 5: Solve for x
    x = 20,988.54/131.21
  6. Step 6: Final answer
    x = 159.96

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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.