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Finding the Fourth Proportional to 140.80, 210.92 and 138.88

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Solution

The fourth proportional to 140.80, 210.92 and 138.88 is: 208.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    140.80 : 210.92 = 138.88 : x
  2. Step 2: Convert to fraction form
    140.80/210.92 = 138.88/x
  3. Step 3: Cross multiply
    140.80x = 210.92 × 138.88
  4. Step 4: Simplify right side
    140.80x = 29,292.57
  5. Step 5: Solve for x
    x = 29,292.57/140.80
  6. Step 6: Final answer
    x = 208.04

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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.