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Finding the Fourth Proportional to 68.81, 103.12 and 28.18

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Solution

The fourth proportional to 68.81, 103.12 and 28.18 is: 42.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.81 : 103.12 = 28.18 : x
  2. Step 2: Convert to fraction form
    68.81/103.12 = 28.18/x
  3. Step 3: Cross multiply
    68.81x = 103.12 × 28.18
  4. Step 4: Simplify right side
    68.81x = 2,905.92
  5. Step 5: Solve for x
    x = 2,905.92/68.81
  6. Step 6: Final answer
    x = 42.23

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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.