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Finding the Fourth Proportional to 52.60, 78.90 and 39.92

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Solution

The fourth proportional to 52.60, 78.90 and 39.92 is: 59.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    52.60 : 78.90 = 39.92 : x
  2. Step 2: Convert to fraction form
    52.60/78.90 = 39.92/x
  3. Step 3: Cross multiply
    52.60x = 78.90 × 39.92
  4. Step 4: Simplify right side
    52.60x = 3,149.69
  5. Step 5: Solve for x
    x = 3,149.69/52.60
  6. Step 6: Final answer
    x = 59.88

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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.