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Finding the Fourth Proportional to 68.82, 103.08 and 28.20

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Solution

The fourth proportional to 68.82, 103.08 and 28.20 is: 42.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.82 : 103.08 = 28.20 : x
  2. Step 2: Convert to fraction form
    68.82/103.08 = 28.20/x
  3. Step 3: Cross multiply
    68.82x = 103.08 × 28.20
  4. Step 4: Simplify right side
    68.82x = 2,906.86
  5. Step 5: Solve for x
    x = 2,906.86/68.82
  6. Step 6: Final answer
    x = 42.24

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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.