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Finding the Fourth Proportional to 108.31, 149.47 and 71.54

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Solution

The fourth proportional to 108.31, 149.47 and 71.54 is: 98.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    108.31 : 149.47 = 71.54 : x
  2. Step 2: Convert to fraction form
    108.31/149.47 = 71.54/x
  3. Step 3: Cross multiply
    108.31x = 149.47 × 71.54
  4. Step 4: Simplify right side
    108.31x = 10,692.34
  5. Step 5: Solve for x
    x = 10,692.34/108.31
  6. Step 6: Final answer
    x = 98.72

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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.