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Finding the Fourth Proportional to 40.20, 60.30 and 39.61

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Solution

The fourth proportional to 40.20, 60.30 and 39.61 is: 59.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    40.20 : 60.30 = 39.61 : x
  2. Step 2: Convert to fraction form
    40.20/60.30 = 39.61/x
  3. Step 3: Cross multiply
    40.20x = 60.30 × 39.61
  4. Step 4: Simplify right side
    40.20x = 2,388.56
  5. Step 5: Solve for x
    x = 2,388.56/40.20
  6. Step 6: Final answer
    x = 59.42

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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.