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Finding the Fourth Proportional to 103.28, 154.61 and 81.23

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Solution

The fourth proportional to 103.28, 154.61 and 81.23 is: 121.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.28 : 154.61 = 81.23 : x
  2. Step 2: Convert to fraction form
    103.28/154.61 = 81.23/x
  3. Step 3: Cross multiply
    103.28x = 154.61 × 81.23
  4. Step 4: Simplify right side
    103.28x = 12,558.40
  5. Step 5: Solve for x
    x = 12,558.40/103.28
  6. Step 6: Final answer
    x = 121.60

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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.