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Finding the Fourth Proportional to 80.17, 120.21 and 39.57

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Solution

The fourth proportional to 80.17, 120.21 and 39.57 is: 59.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.17 : 120.21 = 39.57 : x
  2. Step 2: Convert to fraction form
    80.17/120.21 = 39.57/x
  3. Step 3: Cross multiply
    80.17x = 120.21 × 39.57
  4. Step 4: Simplify right side
    80.17x = 4,756.71
  5. Step 5: Solve for x
    x = 4,756.71/80.17
  6. Step 6: Final answer
    x = 59.33

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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.