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Finding the Fourth Proportional to 40.05, 54.91 and 39.75

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Solution

The fourth proportional to 40.05, 54.91 and 39.75 is: 54.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    40.05 : 54.91 = 39.75 : x
  2. Step 2: Convert to fraction form
    40.05/54.91 = 39.75/x
  3. Step 3: Cross multiply
    40.05x = 54.91 × 39.75
  4. Step 4: Simplify right side
    40.05x = 2,182.57
  5. Step 5: Solve for x
    x = 2,182.57/40.05
  6. Step 6: Final answer
    x = 54.50

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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.