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Finding the Fourth Proportional to 139.21, 208.87 and 62.12

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Solution

The fourth proportional to 139.21, 208.87 and 62.12 is: 93.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.21 : 208.87 = 62.12 : x
  2. Step 2: Convert to fraction form
    139.21/208.87 = 62.12/x
  3. Step 3: Cross multiply
    139.21x = 208.87 × 62.12
  4. Step 4: Simplify right side
    139.21x = 12,975.37
  5. Step 5: Solve for x
    x = 12,975.37/139.21
  6. Step 6: Final answer
    x = 93.21

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.