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Finding the Fourth Proportional to 80.34, 120.54 and 39.69

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Solution

The fourth proportional to 80.34, 120.54 and 39.69 is: 59.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.34 : 120.54 = 39.69 : x
  2. Step 2: Convert to fraction form
    80.34/120.54 = 39.69/x
  3. Step 3: Cross multiply
    80.34x = 120.54 × 39.69
  4. Step 4: Simplify right side
    80.34x = 4,784.16
  5. Step 5: Solve for x
    x = 4,784.16/80.34
  6. Step 6: Final answer
    x = 59.55

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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.