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Finding the Fourth Proportional to 139.30, 208.94 and 47.98

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Solution

The fourth proportional to 139.30, 208.94 and 47.98 is: 71.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.30 : 208.94 = 47.98 : x
  2. Step 2: Convert to fraction form
    139.30/208.94 = 47.98/x
  3. Step 3: Cross multiply
    139.30x = 208.94 × 47.98
  4. Step 4: Simplify right side
    139.30x = 10,024.94
  5. Step 5: Solve for x
    x = 10,024.94/139.30
  6. Step 6: Final answer
    x = 71.97

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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.