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Finding the Fourth Proportional to 139.67, 209.55 and 101.20

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Solution

The fourth proportional to 139.67, 209.55 and 101.20 is: 151.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.67 : 209.55 = 101.20 : x
  2. Step 2: Convert to fraction form
    139.67/209.55 = 101.20/x
  3. Step 3: Cross multiply
    139.67x = 209.55 × 101.20
  4. Step 4: Simplify right side
    139.67x = 21,205.41
  5. Step 5: Solve for x
    x = 21,205.41/139.67
  6. Step 6: Final answer
    x = 151.83

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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.