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Finding the Fourth Proportional to 40.20, 60.60 and 39.60

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Solution

The fourth proportional to 40.20, 60.60 and 39.60 is: 59.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    40.20 : 60.60 = 39.60 : x
  2. Step 2: Convert to fraction form
    40.20/60.60 = 39.60/x
  3. Step 3: Cross multiply
    40.20x = 60.60 × 39.60
  4. Step 4: Simplify right side
    40.20x = 2,399.76
  5. Step 5: Solve for x
    x = 2,399.76/40.20
  6. Step 6: Final answer
    x = 59.70

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.