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Finding the Fourth Proportional to 137.80, 206.65 and 69.30

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Solution

The fourth proportional to 137.80, 206.65 and 69.30 is: 103.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.80 : 206.65 = 69.30 : x
  2. Step 2: Convert to fraction form
    137.80/206.65 = 69.30/x
  3. Step 3: Cross multiply
    137.80x = 206.65 × 69.30
  4. Step 4: Simplify right side
    137.80x = 14,320.85
  5. Step 5: Solve for x
    x = 14,320.85/137.80
  6. Step 6: Final answer
    x = 103.92

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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.