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Finding the Fourth Proportional to 40.08, 60.39 and 38.40

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Solution

The fourth proportional to 40.08, 60.39 and 38.40 is: 57.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    40.08 : 60.39 = 38.40 : x
  2. Step 2: Convert to fraction form
    40.08/60.39 = 38.40/x
  3. Step 3: Cross multiply
    40.08x = 60.39 × 38.40
  4. Step 4: Simplify right side
    40.08x = 2,318.98
  5. Step 5: Solve for x
    x = 2,318.98/40.08
  6. Step 6: Final answer
    x = 57.86

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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.