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Finding the Fourth Proportional to 137.40, 205.95 and 68.85

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Solution

The fourth proportional to 137.40, 205.95 and 68.85 is: 103.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.40 : 205.95 = 68.85 : x
  2. Step 2: Convert to fraction form
    137.40/205.95 = 68.85/x
  3. Step 3: Cross multiply
    137.40x = 205.95 × 68.85
  4. Step 4: Simplify right side
    137.40x = 14,179.66
  5. Step 5: Solve for x
    x = 14,179.66/137.40
  6. Step 6: Final answer
    x = 103.20

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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.