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Finding the Fourth Proportional to 108.86, 150.39 and 87.12

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Solution

The fourth proportional to 108.86, 150.39 and 87.12 is: 120.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    108.86 : 150.39 = 87.12 : x
  2. Step 2: Convert to fraction form
    108.86/150.39 = 87.12/x
  3. Step 3: Cross multiply
    108.86x = 150.39 × 87.12
  4. Step 4: Simplify right side
    108.86x = 13,101.98
  5. Step 5: Solve for x
    x = 13,101.98/108.86
  6. Step 6: Final answer
    x = 120.36

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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.