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Finding the Fourth Proportional to 139.87, 210.85 and 137.77

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Solution

The fourth proportional to 139.87, 210.85 and 137.77 is: 207.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.87 : 210.85 = 137.77 : x
  2. Step 2: Convert to fraction form
    139.87/210.85 = 137.77/x
  3. Step 3: Cross multiply
    139.87x = 210.85 × 137.77
  4. Step 4: Simplify right side
    139.87x = 29,048.80
  5. Step 5: Solve for x
    x = 29,048.80/139.87
  6. Step 6: Final answer
    x = 207.68

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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.