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Finding the Fourth Proportional to 103.17, 154.80 and 102.90

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Solution

The fourth proportional to 103.17, 154.80 and 102.90 is: 154.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.17 : 154.80 = 102.90 : x
  2. Step 2: Convert to fraction form
    103.17/154.80 = 102.90/x
  3. Step 3: Cross multiply
    103.17x = 154.80 × 102.90
  4. Step 4: Simplify right side
    103.17x = 15,928.92
  5. Step 5: Solve for x
    x = 15,928.92/103.17
  6. Step 6: Final answer
    x = 154.39

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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.