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Finding the Fourth Proportional to 80.20, 120.30 and 56.36

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Solution

The fourth proportional to 80.20, 120.30 and 56.36 is: 84.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.20 : 120.30 = 56.36 : x
  2. Step 2: Convert to fraction form
    80.20/120.30 = 56.36/x
  3. Step 3: Cross multiply
    80.20x = 120.30 × 56.36
  4. Step 4: Simplify right side
    80.20x = 6,780.11
  5. Step 5: Solve for x
    x = 6,780.11/80.20
  6. Step 6: Final answer
    x = 84.54

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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.