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Finding the Fourth Proportional to 131.31, 181.24 and 87.05

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Solution

The fourth proportional to 131.31, 181.24 and 87.05 is: 120.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    131.31 : 181.24 = 87.05 : x
  2. Step 2: Convert to fraction form
    131.31/181.24 = 87.05/x
  3. Step 3: Cross multiply
    131.31x = 181.24 × 87.05
  4. Step 4: Simplify right side
    131.31x = 15,778.09
  5. Step 5: Solve for x
    x = 15,778.09/131.31
  6. Step 6: Final answer
    x = 120.16

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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.