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Finding the Fourth Proportional to 40.76, 55.90 and 39.86

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Solution

The fourth proportional to 40.76, 55.90 and 39.86 is: 54.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    40.76 : 55.90 = 39.86 : x
  2. Step 2: Convert to fraction form
    40.76/55.90 = 39.86/x
  3. Step 3: Cross multiply
    40.76x = 55.90 × 39.86
  4. Step 4: Simplify right side
    40.76x = 2,228.17
  5. Step 5: Solve for x
    x = 2,228.17/40.76
  6. Step 6: Final answer
    x = 54.67

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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.