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Finding the Fourth Proportional to 103.40, 154.90 and 80.50

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Solution

The fourth proportional to 103.40, 154.90 and 80.50 is: 120.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.40 : 154.90 = 80.50 : x
  2. Step 2: Convert to fraction form
    103.40/154.90 = 80.50/x
  3. Step 3: Cross multiply
    103.40x = 154.90 × 80.50
  4. Step 4: Simplify right side
    103.40x = 12,469.45
  5. Step 5: Solve for x
    x = 12,469.45/103.40
  6. Step 6: Final answer
    x = 120.59

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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.