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Finding the Fourth Proportional to 108.78, 164.09 and 102.12

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Solution

The fourth proportional to 108.78, 164.09 and 102.12 is: 154.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    108.78 : 164.09 = 102.12 : x
  2. Step 2: Convert to fraction form
    108.78/164.09 = 102.12/x
  3. Step 3: Cross multiply
    108.78x = 164.09 × 102.12
  4. Step 4: Simplify right side
    108.78x = 16,756.36
  5. Step 5: Solve for x
    x = 16,756.36/108.78
  6. Step 6: Final answer
    x = 154.04

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.