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Finding the Fourth Proportional to 108.09, 149.04 and 87.42

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Solution

The fourth proportional to 108.09, 149.04 and 87.42 is: 120.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    108.09 : 149.04 = 87.42 : x
  2. Step 2: Convert to fraction form
    108.09/149.04 = 87.42/x
  3. Step 3: Cross multiply
    108.09x = 149.04 × 87.42
  4. Step 4: Simplify right side
    108.09x = 13,029.08
  5. Step 5: Solve for x
    x = 13,029.08/108.09
  6. Step 6: Final answer
    x = 120.54

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.