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Finding the Fourth Proportional to 68.76, 103.16 and 28.16

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Solution

The fourth proportional to 68.76, 103.16 and 28.16 is: 42.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.76 : 103.16 = 28.16 : x
  2. Step 2: Convert to fraction form
    68.76/103.16 = 28.16/x
  3. Step 3: Cross multiply
    68.76x = 103.16 × 28.16
  4. Step 4: Simplify right side
    68.76x = 2,904.99
  5. Step 5: Solve for x
    x = 2,904.99/68.76
  6. Step 6: Final answer
    x = 42.25

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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.