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Finding the Fourth Proportional to 39.70, 54.33 and 39.30

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Solution

The fourth proportional to 39.70, 54.33 and 39.30 is: 53.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    39.70 : 54.33 = 39.30 : x
  2. Step 2: Convert to fraction form
    39.70/54.33 = 39.30/x
  3. Step 3: Cross multiply
    39.70x = 54.33 × 39.30
  4. Step 4: Simplify right side
    39.70x = 2,135.17
  5. Step 5: Solve for x
    x = 2,135.17/39.70
  6. Step 6: Final answer
    x = 53.78

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.