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Finding the Fourth Proportional to 80.40, 120.60 and 19.53

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Solution

The fourth proportional to 80.40, 120.60 and 19.53 is: 29.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.40 : 120.60 = 19.53 : x
  2. Step 2: Convert to fraction form
    80.40/120.60 = 19.53/x
  3. Step 3: Cross multiply
    80.40x = 120.60 × 19.53
  4. Step 4: Simplify right side
    80.40x = 2,355.26
  5. Step 5: Solve for x
    x = 2,355.26/80.40
  6. Step 6: Final answer
    x = 29.29

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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.