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Finding the Fourth Proportional to 136.31, 204.21 and 87.57

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Solution

The fourth proportional to 136.31, 204.21 and 87.57 is: 131.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    136.31 : 204.21 = 87.57 : x
  2. Step 2: Convert to fraction form
    136.31/204.21 = 87.57/x
  3. Step 3: Cross multiply
    136.31x = 204.21 × 87.57
  4. Step 4: Simplify right side
    136.31x = 17,882.67
  5. Step 5: Solve for x
    x = 17,882.67/136.31
  6. Step 6: Final answer
    x = 131.20

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.