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Finding the Fourth Proportional to 80.90, 121.28 and 29.54

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Solution

The fourth proportional to 80.90, 121.28 and 29.54 is: 44.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.90 : 121.28 = 29.54 : x
  2. Step 2: Convert to fraction form
    80.90/121.28 = 29.54/x
  3. Step 3: Cross multiply
    80.90x = 121.28 × 29.54
  4. Step 4: Simplify right side
    80.90x = 3,582.20
  5. Step 5: Solve for x
    x = 3,582.20/80.90
  6. Step 6: Final answer
    x = 44.28

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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.