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Finding the Fourth Proportional to 108.20, 149.30 and 61.56

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Solution

The fourth proportional to 108.20, 149.30 and 61.56 is: 84.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    108.20 : 149.30 = 61.56 : x
  2. Step 2: Convert to fraction form
    108.20/149.30 = 61.56/x
  3. Step 3: Cross multiply
    108.20x = 149.30 × 61.56
  4. Step 4: Simplify right side
    108.20x = 9,190.91
  5. Step 5: Solve for x
    x = 9,190.91/108.20
  6. Step 6: Final answer
    x = 84.94

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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.