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Finding the Fourth Proportional to 115.38, 158.90 and 102.20

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Solution

The fourth proportional to 115.38, 158.90 and 102.20 is: 140.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    115.38 : 158.90 = 102.20 : x
  2. Step 2: Convert to fraction form
    115.38/158.90 = 102.20/x
  3. Step 3: Cross multiply
    115.38x = 158.90 × 102.20
  4. Step 4: Simplify right side
    115.38x = 16,238.27
  5. Step 5: Solve for x
    x = 16,238.27/115.38
  6. Step 6: Final answer
    x = 140.74

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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.