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Finding the Fourth Proportional to 139.01, 209.26 and 98.72

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Solution

The fourth proportional to 139.01, 209.26 and 98.72 is: 148.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.01 : 209.26 = 98.72 : x
  2. Step 2: Convert to fraction form
    139.01/209.26 = 98.72/x
  3. Step 3: Cross multiply
    139.01x = 209.26 × 98.72
  4. Step 4: Simplify right side
    139.01x = 20,657.65
  5. Step 5: Solve for x
    x = 20,657.65/139.01
  6. Step 6: Final answer
    x = 148.61

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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.