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Finding the Fourth Proportional to 103.31, 155.12 and 99.15

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Solution

The fourth proportional to 103.31, 155.12 and 99.15 is: 148.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.31 : 155.12 = 99.15 : x
  2. Step 2: Convert to fraction form
    103.31/155.12 = 99.15/x
  3. Step 3: Cross multiply
    103.31x = 155.12 × 99.15
  4. Step 4: Simplify right side
    103.31x = 15,380.15
  5. Step 5: Solve for x
    x = 15,380.15/103.31
  6. Step 6: Final answer
    x = 148.87

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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.