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Finding the Fourth Proportional to 139.51, 209.31 and 98.38

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Solution

The fourth proportional to 139.51, 209.31 and 98.38 is: 147.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.51 : 209.31 = 98.38 : x
  2. Step 2: Convert to fraction form
    139.51/209.31 = 98.38/x
  3. Step 3: Cross multiply
    139.51x = 209.31 × 98.38
  4. Step 4: Simplify right side
    139.51x = 20,590.38
  5. Step 5: Solve for x
    x = 20,590.38/139.51
  6. Step 6: Final answer
    x = 147.60

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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.